Manual Therapy Journal - Volume 10, Issue 2, Pages 93-174 (May 2005)

VOLUME 10 NUMBER 2 PAGES 93– 174 MAY 2005

Editors

International Advisory Board

Ann Moore PhD, GradDipPhys, FCSP, CertEd, FMACP Clinical Research Centre for Healthcare Professions University of Brighton Aldro Building, 49 Darley Road Eastbourne BN20 7UR, UK

K. Bennell (Victoria, Australia) K. Burton (Hudders¢eld, UK) B. Carstensen (Frederiksberg, Denmark) E. Cruz (Setubal Portugal) L. Danneels (Mar|¤ akerke, Belgium) S. Durrell (London, UK) S. Edmondston (Perth, Australia) J. Endresen (Flaktvei, Norway) L. Exelby (Biggleswade, UK) J. Greening (London, UK) C. J. Groen (Utrecht,The Netherlands) A. Gross (Hamilton, Canada) T. Hall (West Leederville, Australia) W. Hing (Auckland, New Zealand) M. Jones (Adelaide, Australia) S. King (Glamorgan, UK) B.W. Koes (Amsterdam,The Netherlands) D. Lawrence (Davenport, IA, USA) D. Lee (Delta, Canada) R. Lee (Hung Hom, Hong Kong) C. Liebenson (Los Angeles, CA, USA) L. Ma¡ey-Ward (Calgary, Canada) J. McConnell (Northbridge, Australia) S. Mercer (Dunedin, New Zealand) E. Maheu (Quebec, Canada) D. Newham (London, UK) J. Ng (Hung Hom, Hong Kong) L. Ombregt (Kanegem-Tielt, Belgium) N. Osbourne (Bournemouth, UK) M. Paatelma (Jyvaskyla, Finland) N. Petty (Eastbourne, UK) A. Pool-Goudzwaard (The Netherlands) M. Pope (Aberdeen, UK) G. Rankin (London, UK) D. Reid (Auckland, New Zealand) M. Rocabado (Santiago, Chile) C. Shacklady (Manchester, UK) M. Shacklock (Adelaide, Australia) D. Shirley (Lidcombe, Australia) V. Smedmark (Stenhamra, Sweden) W. Smeets (Tongeren, Belgium) C. Snijders (Rotterdam,The Netherlands) M. Sterling (St Lucia, Australia) R. Soames (Leeds, UK) P. Spencer (Barnstaple, UK) P. Tehan (Victoria, Australia) M. Testa (Alassio, Italy) M. Uys (Tygerberg, South Africa) P. van Roy (Brussels, Belgium) B.Vicenzino (St Lucia, Australia) H.J.M.Von Piekartz (Wierden,The Netherlands) M.Wallin (Spanga, Sweden) M.Wessely(Paris, France) A.Wright (Perth, Australia) M. Zusman (Mount Lawley, Australia)

Gwendolen Jull PhD, MPhty, Grad Dip ManTher, FACP Department of Physiotherapy University of Queensland Brisbane QLD 4072, Australia Editorial Committee Karen Beeton MPhty, BSc(Hons), MCSP (Masterclass Editor) MACP ex o⁄cio member Department of Allied Health Professions—Physiotherapy University of Hertfordshire College Lane Hat¢eld AL10 9AB, UK Je¡rey D. Boyling MSc, BPhty, GradDipAdvManTher, MAPA, MCSP, MErgS (Case reports & Professional Issues Editor) Je¡rey Boyling Associates Broadway Chambers Hammersmith Broadway LondonW6 7AF, UK Tim McClune D.O. Spinal Research Unit. University of Hudders¢eld 30 Queen Street Hudders¢eld HD12SP, UK Darren A. Rivett PhD, MAppSc, MPhty, GradDip ManTher, BAppSc (Phty) (Case reports & Professional Issues Editor) Discipline of Physiotherapy Faculty of Health The University of Newcastle Callaghan, NSW 2308, Australia Kevin P. Singer PhD Centre for Musculoskeletal Studies Department of Surgery The University of Western Australia, Royal Perth Hospital Level 2, MRF Building, 50 rear, Murray Street Perth,WA 6000, Australia Raymond Swinkels MSc, PT, MT (Book Review editor) Ulenpas 80 5655 JD Eindoven The Netherlands

Visit the journal website at http://www.intl.elsevierhealth.com/journals/math doi: 10.1016/S1356-689X(05)00047-0

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Manual Therapy 10 (2005) 93–95 www.elsevier.com/locate/math

Editorial

Manual Therapy Journal 10 year anniversary A warm welcome to this issue of Manual Therapy Journal. The year 2005 sees the 10th anniversary of the journal. The first issue was published in November 1995 and on this occasion, it is timely to recall the origins of the journal, acknowledge the people involved in its production as well as looking to the future.

1. The origins Manual Therapy Journal was conceived in a small coffee shop in Holborn, London on a cold Autumn morning in 1994, when a meeting was held between Ann Moore and Mary Emmerson Law from the publishing house, Churchill Livingstone (Mary Law is well known to many readers of Manual Therapy Journal). Ann was at that time editor of the Manipulative Physiotherapist Journal, the in-house journal of the Manipulation Association of Chartered Physiotherapists (MACP) in the UK, and had been editor of this journal since 1990, having taken on the role from Sarah Wykham. The Manipulative Physiotherapist Journal had grown from a regular two page newsletter that was originally produced by Greg Grieve in the 1980s. The original newsletter was lovingly typed (not word processed!) by Greg’s wife Barbara, and was circulated to members of the MACP by post. Gradually due to Greg and Barbara’s hard work and enthusiasm, the newsletter evolved into a 20 page newsletter, including an editorial, reviews, course advertisements and short articles. It was produced in-house and posted to all subscribers. With the increasing number of members of the MACP, and the newsletter growing in size, in-house printing was no longer an option, and so in the second half of the 1980s’ a new in-house journal, The Manipulative Physiotherapist Journal was developed, which although edited and produced in-house was sent out for printing and then was returned to the editor for posting out to members of the MACP. This was quite a large task for the editor who apart from their own resources and some secretarial input had no other help on the production or editing side. 1356-689X/$ - see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2005.03.002

In the early nineties, the Manipulative Physiotherapist Journal was very short of content. It was difficult to obtain good quality articles. The publishing culture in Musculoskeletal Therapy in the United Kingdom was not strong, and the journal as an in-house journal was not particularly attractive to more experienced authors either in the United Kingdom or on the international scene. Thus, it was very rare at that time to receive unsolicited papers and material was canvassed from conferences with varying success. By 1994, it was concluded that there was no bright future in in-house publishing. If a high-quality journal was to be developed, there would always be resource issues and always be the tendency for authors and researchers to use the in-house journal for research that could not be published elsewhere, and the best scenario would be relying on well-known names in the Manual Therapy world for opinion pieces and/or summaries of their work to date. There were however, a number of Manual Therapists internationally who did contribute to the Manipulative Physiotherapist Journal in this way and who thankfully helped to raise it’s profile and standard to a point where the publishers Churchill Livingstone, were interested in developing and marketing a new international journal for Musculoskeletal Therapists, what we know today as the Manual Therapy Journal. The prospect of a new international journal was an exciting development for both Ann Moore and for the Manipulation Association of Chartered Physiotherapists, but more excitement was to come, in particular, the internationalisation of the journal. The creation of today’s Manual Therapy began with invitations for editorship. Gwen Jull was an obvious choice for coeditorship, with Ann Moore, with her international and strong research profile. Gwen and Ann had not met at all before 1994 and eventually met over coffee, an event arranged by Mary Emmerson Law. (Coffee seems to have featured large in the development of this journal!) The meeting took place at Herriot Watt University in Edinburgh during a Manipulation Association of Chartered Physiotherapists Conference in November 1994, and the meeting really was held to see if Ann and

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Gwen could envisage working together! The meeting went well. Since that date the editors have been in frequent and regular contact by phone and email, and meet up usually at least once a year to discuss journal issues, an arrangement works well. One of the principal ideas behind the development of the international journal, was the hope that many Musculoskeletal Therapists from all over the world would read the journal and through their reading develop a common language and knowledge base in respect of manual therapy. A second driver for the development of an international journal was to raise the standard of publications in the musculoskeletal field and increase exposure to other disciplines. Over the years a large number of high-quality articles have been published in Manual Therapy and because of this and our international perspective, Manual Therapy has been included in all the major citation indices, for example Index Medicus/Medline, CINHAL, Amed. For the last 2 years Manual Therapy Journal has been awarded an impact factor, which has risen to its current status of 1.189. This is an indication of how much the journal content is cited in other journals and in other articles within the journal itself. It is now ranked 6th in the rehabilitation journals. In addition, full text articles downloads from the Manual Therapy website have increased phenomenally from 9000 in 2002 to 62,143 in the most recent audit. This is a phenomenal increase in interest in the Journal.

2. Recognition of the Editorial Advisory Board and Journal Reviewers As editors we are very proud of these achievements, but these successes are not at all due to the editors alone. The successes are due to a large team effort that involves a great number of people across the world, and so for this reason many warm thanks are due from the editors to Members of the current Editorial Board—Karen Beeton, Jeff Boyling, Raymond Swinkels, Kevin Singer and Darren Rivett, Members of the original Editorial Board in 1995, Roger Soames and Clive Standen and new Board member, Tim McClune. All of these individuals have given many hours of devoted work in producing Manual Therapy on a regular basis. They help develop the policies and procedures for the journal, review manuscripts and books on a regular basis as well as promote the journal whenever possible in their own countries and at international conferences and events. Thanks also go to all those individuals not directly affiliated to the journal who review papers, as without high-quality reviewers, the standard of the journal would not be as high as it is. The reviewers share in the success of the today’s journal.

3. Recognition of the production team Acknowledgement is also given to a host of individuals on the production side of the journal who work behind the scenes to ensure that the journal is published. In particular, thanks go to Mary Emmerson Law, originally from Churchill Livingstone, but now part of Elsevier Science, who had the original confidence in the journal to take it into the Churchill Livingstone portfolio of journals, and who has given both editors and the Editorial Board a tremendous amount of personal support over the years. Additionally, many thanks go to Barbara Muir, Mary Law’s secretary for her efficiency in the early days and her ‘‘wee anecdotes’’ from Edinburgh that brightened some dark days on the publishing front from time to time. Acknowledgement and thanks go to all Churchill Livingstone and latterly Elsevier staff who have contributed to the journal in terms of editorial management, editorial support, production and marketing and who have worked with us consistently over the years to sustain the journal and its growth. In particular, Melanie Tait is acknowledged. She always seems to have a solution to the problem in hand and also gives a considerable amount of personal support to the, editors. Sarah Davis, Jacqui Braney and Jo Merrett have been in day to day contact with us as editors over the last few years. Thanks also go to those involved in local journal administration support over the years and these include Sara Hester, Denise Scott Fears, Jayne Ingles and Nicky Pont and to the dozens of staff at Elsevier Science who are involved in the journal production and editing process who we never meet or see, but are very much appreciated for all the work done behind the scenes.

4. Recognition of the authors All contributors to the journal over the last 10 year period are especially acknowledged for it is the manuscripts that make the journal. Also without the contributors the evidence base of Manual Therapy would not be growing at the speed at which it is growing to date. Thank you very much for wishing to publish in Manual Therapy Journal and we hope you will publish with us again in the near future.

5. Recognition of the readers Thanks are due to the readership and subscribers, without whose support there would be no journal. We would like to encourage you to contribute to the scholarly debate within the journal by writing to the editors about issues of importance to Musculoskeletal Therapists in your locality and also with constructive

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comments on the academic papers that are published in the journal. We hope you will continue reading Manual Therapy Journal.

6. The future And so to the future of the journal and its goals. Some of these may be summarised as follows:

    

A continued presence as a high-quality international journal. Further expansion of the science and evidence base of musculoskeletal therapy. An increasing number of high-quality contributions. An increase in the number of journal issues per year. A widening readership.

 

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A continuous increase in impact factor status. The satisfaction of all our stakeholders.

Manual Therapy Journal will celebrate its 10th anniversary in September 2005 at the MACP/Kinetic Control Conference to be held in Edinburgh, as advertised in this journal. We hope to see many of you there and to share in the celebrations. Our thanks and cheers to all. Ann Moore, Gwen Jull (Co-editors) University of Brighton, Aldro Building, 49 Darley Road, Eastbourne, East Sussex, BN20 7UR, UK E-mail address: [email protected] (A. Moore)

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Manual Therapy 10 (2005) 96–107 www.elsevier.com/locate/math

Masterclass

The management of hamstring injury—Part 1: Issues in diagnosis Wayne Hoskins, Henry Pollard Macquarie Injury Management Group, Macquarie University, Sydney, Australia Received 24 December 2004; accepted 10 March 2005

Abstract Hamstring injuries are the most prevalent muscle injury in sports involving rapid acceleration and maximum speed running. Injury typically occurs in an acute manner through an eccentric mechanism at the terminal stages of the swing phase of gait. Biceps femoris is most commonly injured. Re-injury rates are high and management is a challenge given the complex multi-factorial aetiology. The high rates of hamstring injury and re-injury may result from a lack of high-quality research into the aetiological factors underlying injury. Re-injury may also result from inaccuracy in diagnosis that results from the potential multi-factorial causes of these conditions. Inaccuracy in diagnosis could lead to multiple potential diagnoses that may result in the implementation of variable management protocols. Whilst potentially useful, such variability may also lead to the implementation of sub-optimal management strategies. Previous hamstring injury is the most recognized risk factor for injury, which indicates that future research should be directed at preventative measures. Much anecdotal and indirect evidence exists to suggest that several non-local factors contribute to injury, which may be addressed through the application of manual therapy. However, this connection has been neglected in previous research and literature. This paper will explore and speculate on this potential connection and offer some new contributive factors for hamstring injury management. This first paper of a two part series on hamstring injury will explore diagnostic issues relevant to hamstring injury and the second will investigate various established and speculative management approaches. r 2005 Elsevier Ltd. All rights reserved. Keywords: Hamstring; Sports injury; Muscle strain; Diagnosis

1. Introduction Hamstring injuries are common in all sports requiring rapid acceleration and maximum speed running. Injury surveillances have found hamstring injuries to be the most common injury in athletics (especially in sprinters) (McLennan and McLennan, 1990; Bennell and Crossley, 1996), soccer (Woods et al., 2004), Australian Rules football (Orchard and Seward, 2002), cricket (Orchard et al., 2002a; Stretch, 2003), touch football (Neumann et al., 1998) and hurling (Watson, 1996), whilst they are Corresponding author. Macquarie Injury Management Group, C/o PO Box 448, Cronulla, NSW 2230, Australia. Tel.: +61 29523 4600; fax: +61 29527 3856. E-mail address: [email protected] (W. Hoskins).

1356-689X/$ - see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2005.03.006

very common in rugby league (Gabbett, 2003) and rugby union (Targett, 1998). Using an injury definition as that preventing player participation in a match, as a percentage of total injuries occurring, prevalence has been measured between 11% (Stretch, 2003) and 15% (Orchard et al., 2002a) in cricket, 11% (Dadebo et al., 2004) and 12% (Woods et al., 2004) in soccer and 16% in Australian Rules football (Orchard and Seward, 2003). In terms of injury incidence, approximately 6 players out of each squad will injure a hamstring each season in professional soccer (Woods et al., 2004) and Australian Rules football (Orchard and Seward, 2003). With regards to severity, injury will cause a player to miss approximately 3 matches or weeks of play (Orchard and Seward, 2003; Woods et al., 2004). Given the high incidence of hamstring injuries, diagnosis of

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injury and identification of underlying risk factors is essential in directing treatment and management efforts. Additionally from a monetary perspective, high net worth professional athletes and clubs that employ them may potentially loose a significant amount of income in the time lost to these injuries. Identification and elimination or reduction of risk factors and the application of evidenced based management strategies would likely reduce the burden on the players and the system that supports them. This article will use the current available evidence to document the aetiological factors and pathogenesis behind hamstring injuries. It will identify and speculate on potential local and non-local factors, which may be important in hamstring injury risk that may be addressed through the application of manual therapy. Particular focus will be given to non-local spinal aetiologies of hamstring dysfunction and injury. In presenting this article the Medline, Mantis, Sports Discus, Pedro, Cochrane and Cinahl databases were reviewed (from inception to present) with the following key words: hamstring, injury, treatment, prevention. All papers were considered in the review, as few high-quality studies were available for comment.

2. Anatomy and biomechanics The hamstring muscle group comprises semitendinosus and semimembranosus medially and biceps femoris, short and long heads, laterally. All muscles attach proximally to the ischial tuberosity, except for the short head of biceps femoris, which originates at the linea aspera and lateral supracondylar line of the femur (Moore and Dalley, 1999). Semitendinosus attaches to the medial surface of the superior tibia, semimembranosus to the posterior part of the medial condyle of the tibia and the oblique popliteal ligament, while biceps femoris attaches to the lateral side of the fibula (Moore and Dalley, 1999). Because of this attachment, it has been suggested that the superior tibial-fibula joint should be assessed in hamstring injuries (Woods et al., 2004). Biceps femoris also has strong fascial connections to peroneus longus at the fibula (Weinert et al., 1973), linking it to the action of the ankle and foot (Fig. 1). At the ischial tuberosity, the tendon of the long head of bicep femoris is continuous with the superficial and distal part of the sacrotuberous ligament, which passes across the sacrum and attaches to the thoracolumbar fascia (TLF) (Vleeming et al., 1995) (Fig. 2). The TLF, via its attachments to the latissimus dorsi, transversus abdominus, internal oblique and rhomboid muscles, splenius capitis and cervicus tendons and lumbar vertebrae and posterior superior iliac spines (Bogduk and McIntosh, 1984; Pool-Goudzwaard et al., 1998; Barker and Briggs, 1999; Barker et al., 2004), function-

Fig. 1. Fascial connections of biceps femoris to peroneus longus, which functionally links the hamstrings to the foot and ankle.

ally connects the hamstrings to the lumbar–pelvic spine, upper torso, shoulder and skull (Fig. 3). In cadaveric specimens, contracture of the muscular attachments of the TLF are capable of causing its displacement (Vleeming et al., 1995; Barker and Briggs, 1999; Barker et al., 2004; Van Wingerden et al., 2004), while hamstring tension can tighten the TLF and reduce motion at the sacroiliac joint (SIJ) (Vleeming et al., 1989a, b; Van Wingerden et al., 2004). From the proximal perspective the aponeurosis of the transversus abdominus is continuous with the middle portion of the TLF (Bogduk and Macintosh, 1984; McGill and Norman, 1988). These fibres are then continuous with the lateral raphe and hence the internal oblique muscles (Vleeming et al., 1995; Macintosh et al., 1987). The extensive attachments of transversus abdominus to the TLF combined with its advantageous line of attachment, makes it one of the most capable of all muscles in tensioning the TLF (Hodges and Richardson, 1997). This has been verified by the finding that low levels of tension are effectively transmitted between the transverus abdominus and TLF (Barker et al., 2004). It has been hypothesized that the lateral forces generated by transversus abdominus and the internal obliques

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attaching to the TLF at the lateral border are capable of causing the posterior spinous processes to move together to stabilize intersegmental movement of the lumbar spine (Gracovetsky et al., 1981; Barker et al., 2004) (Fig. 4). The latissimus dorsi has a large attachment and therefore carries a great potential to pretension the TLF (Macintosh et al., 1987; McGill and Norman, 1988; Barker et al., 2004). In support of this contention, it has been demonstrated that traction of the latissimus dorsi can cause between 2 and 10 cm of upward displacement of the TLF (Vleeming et al., 1995). However, the ability of latissimus dorsi to stabilize the SIJ through the TLF has been questioned by other authors (Bogduk et al., 1998). The effect of TLF tension is transmitted to the SIJ from the deep fibres which are connected to the sacrotuberous ligaments (Vleeming et al., 1995). Tension in the TLF could therefore generate forces perpendicular to the SIJ that would stabilize the joint (Vleeming et al., 1995). Others have suggested that due to the welldeveloped lattice of strong collagen fibres, the function of the TLF is as an extensor muscle retinaculum, or nature’s back belt (Bogduk and Macintosh, 1984).

Fig. 2. Continuation of the long head of biceps femoris to the superficial part of the sacrotuberous ligament, which passes across the sacrum and attaches to the thoracolumbar fascia.

Fig. 3. Attachment of the thoracolumbar fascia to latissimus dorsi, which functionally links the hamstrings with the shoulder and upper torso.

Fig. 4. The transversus abdominus through its attachment to the lateral raphe pulls onto the thoracolumbar fascia. The angulation of the deep and superficial layers of the thoracolumbar fascia are hypothesized to create a net force tending to approximate the lumbar vertebrae.

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Whilst being accepted that the TLF is involved in enhancing lumbar–pelvic stability, it is still unclear of how exactly it achieves this. It should also be noted that results have not been proven to be present in a population in vivo as yet. If the results can be generalized, such references provide some scope to hypothesize that the back and/or pelvis may contribute to hamstring injury. Due to the anatomical link between the hamstrings, lumbar spine, pelvis and sacrum, it has been recommended that the biomechanics of these structures be assessed when evaluating hamstring pain (Woods et al., 2004). Semimembranosus has expansions extending to knee joint capsule and the medial menisco-tibial and meniscofemoral formations (Bejui et al., 1984). The anatomical attachments of semimembranosus functionally links it to the popliteus muscle and knee joint (Beltran et al., 2003). The hamstring group is linked to the knee through the hamstring—anterior cruciate ligament (ACL) arc (Osternig et al., 1995; Tsuda et al., 2001). Proprioceptive feedback from ACL mechanoreceptors (Tsuda et al., 2001) and afferent input from skin and muscles (Duysens et al., 1998; Christensen et al., 2000) are postulated to play an important role in hamstring activation during gait, especially at the end stage of the swing phase. Proprioception is important to constantly monitor the progress and sequence of movements and to allow modification of succeeding motor behaviour (Nichols et al., 1999). As proprioceptive deficiency is known to occur following ACL injury (Roberts et al., 1999), this may explain why a previous history of knee injury has been found to be a significant risk factor for hamstring injury (Verrall et al., 2001). Given the functional anatomy of the hamstrings, the full kinetic and kinematic chain should be assessed with injury.

3. Diagnosis, prognosis and severity Diagnosis is based on the typical injury mechanism and clinical findings of local pain and loss of function, demonstrated by palpation, range of motion and muscle testing (Kujala et al., 1997). Sonography, computer tomography and magnetic resonance imaging (MRI) can provide information on the extent of injury (Brandser et al., 1995), with MRI being the most sensitive (Speer et al., 1993). Imaging is more likely to be performed on elite athletes, when there is severe pain and no obvious mechanism of injury, or if the patient is not responding to treatment (Brandser et al., 1995). A plain X-ray may be requested initially to screen for acute avulsion of the ischial apophysis, particularly in adolescent athletes (Brandser et al., 1995). Hamstring injuries associated with T2 muscle hyperintensity present on MRI are associated with longer recovery than hamstring injuries with normal scans

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(Verrall et al., 2003; Gibbs et al., 2004). MRI has been able to predict prognosis by using the degree of crosssectional damage (Pomeranz and Heidt, 1993; Yamamoto, 1993; Slavotinek et al., 2002). The use of crosssectional damage has not been found to be a reliable predictor for future injury though (Gibbs et al., 2004). Further research is needed to aid diagnosis, treatment and help predict when an athlete can safely return to competition. The severity of injury is described by three grades. This imprecise system of classification rates injury disability and assists in prognosticating the length of a typical rehabilitation program. The length of rehabilitation is proportional to the degree of disability, grade of injury and location (Garrett et al., 1984).

4. Location of injury Hamstring strain classically occurs proximal to the distal muscular–tendon junction where force is concentrated (Kirkendall and Garrett, 2002; Slavotinek et al., 2002). This has implications for the length of rehabilitation, as injuries to the tendon or muscular–tendon junction are worse than the muscle belly due to the limited blood supply (Garrett et al., 1984). Biceps femoris has consistently been found to be the most commonly injured of the hamstring muscle group (Garrett et al., 1989; Garrett, 1996; De Smet and Best, 2000; Slavotinek et al., 2002; Koulouris and Connell, 2003; Woods et al., 2004), although multiple injury locations are also possible (De Smet and Best, 2000). Biceps femoris could possibly be predisposed to injury due to its myo-fascial attachments, with injury occurring at the weak point of the kinetic chain. However, whilst sprinting biceps femoris has the greatest respective muscle tendon length of the hamstring muscle group, which may also predispose injury (Thelen et al., 2005). Semitendinosus, semimembranosus and the long head of biceps femoris are innervated by the tibial division of the sciatic nerve and the short head of biceps femoris is innervated by the common peroneal division of the sciatic nerve (Moore and Dalley, 1999). The dual innervation of biceps femoris has been suggested as a causative factor for hamstring injury (Burkett, 1970). Whilst this has been proposed as a potential contributing factor, no evidence exists to support this supposition.

5. Aetiology of injury Hamstring injuries occur distinctively via a strain method in an acute mechanism, which may represent a continuum of injuries from delayed onset muscle soreness (DOMS) and partial strain to complete muscle

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rupture (Kujala et al., 1997). Injury surveillance and reports have found injury to classically occur when accelerating or running at maximum speed (Sherry and Best 2004; Woods et al., 2004). Hamstrings have a relatively high proportion of fast twitch type II muscle fibres which are capable of producing large forces (Garrett et al., 1984; Noonan and Garrett, 1999). Due to their biarticular nature, hamstrings are susceptible to strain during powerful eccentric muscle contractions (Brockett et al., 2004). Muscle injury has been found to predominantly affect type II fibres after intensive eccentric activity like sprinting (Lieber and Friden, 1988; Brockett et al., 2002). Substantial hamstring eccentric contraction occurs late in the swing phase of gait when the hamstrings decelerate hip flexion and knee extension (Montgomery et al., 1994), which is believed to be the most common stage of injury occurrence (Verrall et al., 2001). Such ballistic open chain situations are known to preferentially recruit multi-joint muscles like the hamstrings (Richardson and Bullock, 1986). Hamstring injury may also occur at the initial stage of the stance phase of gait, when hamstring muscle activity is high (Orchard, 2002). This method of injury could be more likely in athletes with poor technique or gluteus maximus weakness or activation problems, as gluteus maximus should be the primary hip extensor in sprinting (Simonsen et al., 1985). During sprinting, the hamstrings should act as a transducer of power between the knee and hip joint and contribute little to hip extension (Jacobs et al., 1996). This transfer of power is essential in the execution of explosive movements like sprinting (Gregoire et al., 1984). Significant alterations to hip extensor recruitment are known to occur with chronic low back pain during walking, causing the gluteus maximus to be inhibited and hamstrings overactive (Vogt et al., 2003). Hypothetically, gluteus maximus

inhibition during sprinting may require the hamstrings to contribute more force to hip extension rather than acting in its transducer role, potentially predisposing injury. However, hip extensor recruitment in back pain subjects has not been measured in a sprinting situation. As speed of gait increases, the amount of stance phase decreases (Mann and Hagy, 1980), which will require more precise lumbar–pelvic neuromuscular control to minimize energy expenditure and maximize running efficiency. The lumbar erector spinae muscles are most active during the initial stages of stance (Thorstensson et al., 1982) and it may be that weakness or activation deficiencies of these muscles compromises lumbar intersegmental functional stability about the neutral zone. Control of intersegmental motion around the neutral zone has been hypothesized as a major parameter of functional spinal instability (Panjabi, 1992), predominantly because motion occurs in this physiological region. The neutral zone increases its range of motion as one of the first indicators of joint injury onset (Oxland and Panjabi, 1992). Furthermore, delayed activation (Hodges and Moseley, 2003), atrophy (Hides et al., 1996), fatigability and decreased endurance (Biedermann et al., 1991) of the multifidus muscles have been noted after low back pain situations which will affect its ability to provide a coordinated contraction for spinal stability about the neutral zone. Following pain and in pain-free situations, increased threshold (Hodges et al., 2003) and delayed activation of transversus abdominus has been documented (Hodges and Richardson, 1998), whilst earlier activation of biceps femoris is noted (Hungerford et al., 2003). This may potentially create a situation where biceps femoris contracts to stabilize the TLF system in compensation, which would increase the likelihood of injury. Therefore, lumbar– pelvic dysfunction may indirectly link aberrant function

Table 1 The concept of scar formation after injury Stages of scar formation

Characteristics

References

Acute inflammatory phase— edema and hemorrhage.

Muscle is weaker and risks further injury. Immobilization is needed to accelerate formation of the granulation tissue matrix and to limit the size of the connective tissue area formation. Scar tissue remains immature and weak and regains strength as long as re-injury does not occur. If worked too hard, injury results.

Kellett (1986), Garrett (1990), Lehto and Jarvinen (1991), Jarvinen and Lehto (1993), Jarvinen et al. (2000), De Smet and Best (2000), Kannus et al. (2003) Kellett (1986), Garrett (1990), Lehto and Jarvinen (1991), Garrett (1996), Buckwalter (1996), Kirkendall and Garrett (2002), Kannus et al. (2003) Kellett (1986), Garrett (1990), Jarvinen and Lehto (1993), Jarvinen et al. (2000), Kannus et al. (2003)

Proliferative phase—early laying down of scar tissue and muscle fibre regeneration. Remodeling phase—scar tissue matures and muscle fibres continue to regenerate.

Scar tissue is inelastic compared with normal tissue and creates a difference in tissue extensibility. Breaks occur at the interface of old and new tissue. Mobilization is required to allow better alignment of muscle fibre through the connective tissue, to promote scar absorption and to minimize atrophy, loss of strength and extensibility, which rapidly appear after prolonged immobilization.

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It is believed that some of the risk factors associated with injury recurrence are in all probability, already implicated with the initial injury (Croisier, 2004). However, it has been stated that there is a paucity of research relating to the real causes of repetitive hamstring injury (Croisier, 2004). Re-injury can result from the inability to assess the severity of initial damage and premature return to competition as athletes return during the remodeling phase of repair. This can be explained by the concept of scar formation after injury in Table 1. With ineffective treatment, scar tissue and adhesions will accumulate and may predispose re-injury. As previously injured muscle is more susceptible to eccentric damage than uninjured muscle (Brockett et al., 2004), future research needs to be directed at preventative measures. Due to the plasticity of the nervous system, recurrent hamstring injuries have been hypothesized to possibly lead to sensitization of the dorsal horn of the spinal cord (Turl and George, 1998), which may predispose injury by altering hamstring and gluteus maximus firing patterns (Lehman et al., 2004).

isokinetic variables could identify previous hamstring injury whereas the eccentric ratio could (Dauty et al., 2003). However, eccentric testing may not be reliable as injury can occur and cause sub-maximal efforts as a protective mechanism (Orchard et al., 2001). The ratio can also differ for athletes across different sports, depending on the testing method (Read and Bellamy, 1990). This is possibly because sprinting and running at slower speeds require different muscle actions and amounts of muscle activity (Mero and Komi, 1987) and different sports require different power requirements (Read and Bellamy, 1990). Some studies have shown strength deficiencies to be significantly associated with injury (Yamamoto, 1993; Orchard et al., 1997), while another larger study did not (Bennell et al., 1998). Strength deficits have been found to exist in athletes with a history of recurrent strains (Jonhagen et al., 1994; Croisier et al., 2002). This may be due to ineffective rehabilitation or dysfunction in the lumbar spine, SIJ or pelvis which has remained uncorrected. However, other studies have reported normal strength after injury (Paton et al., 1989; Worrell et al., 1991). There is insufficient evidence to suggest that hamstring weakness or hamstring:quadricep imbalance is a risk factor for injury due to the conflicting evidence present.

6. Risk factors for injury

6.2. Warm up

Several factors have been hypothesized to be a risk for hamstring injury. This includes hamstring muscle strength and balance, warm-up, fatigue, flexibility, body mechanics, sports specific activities, psychosocial factors and running technique. Injury may occur due to a single factor but is likely to be more the result of an interaction between several factors, which suggests a multimodal and multidisciplinary approach is necessary. Identification of risk factors leading to injury is required for the development of preventative strategies. More long-term prospective epidemiological studies are required to establish what aetiological factors exist and their relative importance in injury causation.

Warm up before activity has been emphasized to prevent muscle injury (Garrett, 1990). Despite this, hamstring strains still occur after significant warm up (Verrall et al., 2003). Moist heat pack application, which may simulate a warm-up situation, has been found not to significantly affect hamstring muscle flexibility (Sawyer et al., 2003). This provides indirect evidence for a kinetic chain and not a local muscle cause of injury. Animal studies have shown that a warm up of isometric contractions increases the amount of force and length of stretch that the muscle can absorb prior to tearing (Safran et al., 1988). A decrease in muscle stiffness with warming is also known to occur (Strickler et al., 1990; Noonan et al., 1993), which increases the muscle length to failure, making the muscle more resistant to stretch induced injuries. Warm up procedures would appear to be of benefit for injury prevention, but a lack of literature exists identifying best practices. Lumbar spine compliance and flexibility has been found to increase with warm up procedures, but it can be lost by 20 min of sitting (Green et al., 2002). This has implications for the attachment of the hamstrings to the TLF and the various spine-hamstring reflex mechanisms that exist, particularly for athletes taking a half time break or sitting on the interchange bench during play.

in the lumbar spine to lumbar–pelvic pain and thence to hamstring injury. 5.1. Recurrent injury

6.1. Muscle strength and balance Several authors have suggested injury to be related to relative weakness and hamstring:quadricep muscle imbalance (Burkett, 1970; Christiensen and Wiseman, 1972; Heiser et al., 1984). Various hamstring:quadricep strength ratios have been proposed, but it remains unclear whether strength disorders are the consequence of injury, a causative factor for injury, or both. It is unclear what testing is best; concentric or the more functional eccentric testing method (Aagaard et al., 1998). One study failed to show that concentric

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6.3. Fatigue

6.4. Flexibility

Muscle fatigue may be important in the pathogenesis of hamstring injury (Heiser et al., 1984; Hawkins and Fuller, 1999; Verrall et al., 2003). Multiple factors are associated with muscle fatigue, including the central and peripheral nervous systems’ and local factors (Roberts and Smith, 1989; Wong et al., 1990). This includes reduction in glycogen content of muscle fibres (Baldwin et al., 1999; Febbraio and Dancey, 1999), increased neural activation to fatigued muscles when sprinting (Nummela et al., 1994) and alterations in central nervous system neurotransmitters and neuromodulators that alter psychic or perceptual state (Newsholme et al., 1992; Davis and Bailey, 1997). Hamstring fatigue induced by repeated efforts of maximal sprint running causes a significant change in running technique (Pinniger et al., 2000), which may contribute to injury. The role of muscle fatigue in an animal model has been discussed and identified as a factor in injury causation (Lieber and Friden, 1988; Mair et al., 1996). Fatigued muscle is less able to produce force than non-fatigued muscle (Mair et al., 1996) and is thus more susceptible to stretch injury in eccentric contractions. When the external force exceeds the internal force production capacity, it is likely that the muscle will begin to elongate whilst still contracting. The resulting eccentric contraction may be large enough to predispose injury, a factor known to be associated with hamstring injury. Fatigue is also known to result in decreased lower extremity (Johnston et al., 1998; Miura et al., 2004) and lumbar–pelvic proprioceptive acuity (Taimela et al., 1999), which potentially could contribute to hamstring injury through deficient neuromuscular motor control and inappropriate muscular contraction. Only one elite sporting competition injury surveillance, performed by the English Premier League soccer, recorded the timing of hamstring injuries in matches (Woods et al., 2004). They found a significant increase in injury at the end of each half, suggesting fatigue or repetitive mictrotrauma was a causative factor. A surveillance of 30 professional soccer clubs found similar results, with two thirds of hamstring strains occurring late in training or matches (Dadebo et al., 2004). A report on 140 hamstring strains found they usually occur early or late in practice or matches, suggesting warm up may also contribute (Dornan, 1971). The timing of hamstring injury should be included in future injury surveillances by different organizations to determine conclusively whether lack of warm up, breaks in play (such as half time or time on the interchange bench), fatigue or accumulative microtrauma significantly contribute to hamstring injury.

Poor flexibility has not been conclusively linked to a risk of hamstring injury. Some prospective evidence exists linking poor flexibility to hamstring injury (Witvrouw et al., 2003), as does some retrospective evidence performed on athletes with a history of injury (Worrell et al., 1991; Jonhagen et al., 1994). However, other studies have found no relationship (Ekstrand and Gillquist, 1983; Hennessey and Watson, 1993). One study showed that a stretching program could statistically reduce hamstring injuries (Hartig and Henderson, 1999). One large study calculated that soccer players who stretch more frequently are of a significantly decreased risk of hamstring strains (Dadebo et al., 2004). Large prospective studies using poor flexibility as a predictor for injury and flexibility programs as a preventative measure for hamstring injury are required. 6.5. Body mechanics Aberrant lumbar–pelvic mechanics has been indirectly linked to possibly playing a role in hamstring injury. Decreased hip flexor and quadriceps flexibility has been identified as a risk factor for hamstring injury (Gabbe et al., 2005), while in a small study, increased unilateral anterior ilium tilt was found to be a risk factor for hamstring injury (Cibulka et al., 1986). Significant excessive lumbar lordosis has been found retrospectively in a group of athletes with previous hamstring injury when compared to a control group with no injury history (Hennessey and Watson, 1993). In a prospective study, excessive lumbar lordosis and sway back were related to thigh muscle strains (hamstring, quadriceps and adductor) and defects in body mechanics were anatomically associated with the site of injury (Watson, 1995). Another prospective study found postural defects to be a significant risk factor for lower limb muscle injuries anatomically associated with the site of injury (Watson, 2001). In the same study, maximum acceleration over 10 m was also a risk factor for hamstring injury. The author concluded that faster (usually more elite) athletes in particular need to take steps to minimize postural defects to prevent injury. The predictable pattern of muscular imbalance known as the lower crossed syndrome, which produces tightness of the hip flexors and lumbar erector spinae and weak, inhibited gluteal and abdominal muscles can result in an anterior pelvic tilt, increased hip flexion and a hyperlordosis of the lumbar spine (Janda, 1996). An increased thoracic kyphosis with decreased thoracic mobility in extension has also been suggested to result in an anterior pelvic tilt (Leibenson, 2001). The altered biomechanics of an anterior pelvic tilt will change the hamstring biomechanics and function and also effect the fascial attachments to the upper torso (Fig. 5). This suggests

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2002b). This makes the kicking action unlikely to be responsible for injury. In cricket, fast bowling workload is a risk for hamstring strains (Orchard et al., 2002a). The unique bowling action may contribute to injury, but injury surveillances have not recorded whether injury occurs during the run up or delivery phase, or to which leg. 6.7. Psychosocial factors

Fig. 5. The fascial relationship of splenius capitus and cervicus with biceps femoris, which functionally links the hamstrings to the skull and upper torso. Also shown is the line of force generated by latissimus dorsi to the thoracolumbar fascia.

The psychosocial model as a causative and contributing factor for pain is well established (Nahit et al., 2003; Keefe et al., 2004). It has been suggested that this model should be researched as a contributing factor for hamstring strains (Sutton, 1984), although no work has yet been performed. Athletes encounter physiological, psychological and social stress (Kentta and Hassmen, 1998). It is known that stress or mental pressure leads to an increase in muscle tension and negatively effects physical performance, including diminished fine motor control and fatigue (Gould et al., 1999; Visser et al., 2004). This could be a problem for an athlete who is already tight through the hamstrings, pelvis or low back and may predispose injury as appropriate proprioceptive feedback is required for correct hamstring contraction, particularly at the terminal stages of the swing phase of gait. Stress also causes an increase in interleukin-6 which leads to a pro-inflammatory state (Orshal and Khalil, 2004), which may affect healing rates and recovery. Prospective psychosocial assessment should be conducted to assess whether it is a predictor for hamstring injury. 6.8. Running technique

treatment of hamstring injuries should be also directed at non-local hamstring factors. However, even if proven to be a risk factor for injury, it is unclear as to whether improving lumbar–pelvic or body mechanics will result in injury prevention. Only one case report could be identified, which provided positive results from improving body and lumbar–pelvic mechanics in association with hamstring soft tissue (Hoskins and Pollard, 2005). Prospective hamstring studies assessing the effectiveness of improving lumbar–pelvic mechanics and looking at the relationship of body posture, pelvic tilt, leg length and scoliosis to injury is warranted. 6.6. Sports specific activities The kicking action has been used to explain the high rates of hamstring injuries in soccer and Australian Rules football. However, there is no significant injury rate in the kicking and non-kicking legs in soccer (Witvrouw et al., 2003; Woods et al., 2004) or Australian Rules football players (Orchard et al.,

The role of running technique in hamstring injury has been neglected in previous hamstring literature. Anecdotally, a common mechanism of injury occurs when the body is leaning forward trying to maintain or achieve extra speed and over striding occurs (Orchard, 2002). Forward lean is counter-productive to sprinting performance (Kunz and Kaufmann, 1981). Gluteus maximus weakness results in a characteristic forward lean lurch, which may result in over striding. Due to their biarticular nature, leaning forward will predispose hamstring injury by increasing its relative length. This would suggest improving motor patterns and running technique may play a role in the management of hamstring injury. Increased lumbar erector spinae activity is also required with forward lean gait (Carlson et al., 1988). Lumbar erector spinae recruitment is known to alter with lumbar–pelvic dysfunction (Hungerford et al., 2003; Hodges and Moseley, 2003), which links optimal lumbar–pelvic function to injury prevention. Further study assessing whether poor technique is implicated in hamstring injury is required as well as

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whether correction or improvement correlates with a reduced injury risk.

7. Conclusions Given the high incidence of hamstring injuries, rates of recurrence and costs involved, future research should investigate risk factors for injury and re-injury. Identification of aetiological factors and their subsequent diagnosis is required in long term prospective epidemiological studies performed at different grades of play across different sports. This could potentially lead to improved player injury management, research and ultimately injury prevention. It would appear that several non-local factors potentially contribute to hamstring injury. Despite much anecdotal and indirect evidence, further research should specifically target this proposed association.

Acknowledgements No source of funding was used in the preparation of this manuscript. The authors have no conflict of interest that is directly relevant to the content of this manuscript.

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Manual Therapy 10 (2005) 108–115 www.elsevier.com/locate/math

Original article

Size and shape of the posterior neck muscles measured by ultrasound imaging: normal values in males and females of different ages G. Rankina,, M. Stokesa,b, D.J. Newhamc a

Royal Hospital for Neuro-disability, London, UK School of Health Professions and Rehabilitation Sciences, University of Southampton, UK c Centre for Applied Biomedical Research, GKT School of Biomedical Sciences, King’s College London, UK b

Received 2 April 2004; received in revised form 30 July 2004; accepted 27 August 2004

Abstract Measurements of muscle strength or size are valuable indicators of muscle status in health and disease. When force cannot be measured directly, due to a particular muscle being one of a functional group or because of pain, size measurements may be the only option. For such data to be useful, normal values for age and gender are necessary. Procedures for scanning and measuring semispinalis capitis and the deep posterior neck muscles (semispinalis cervicis, multifidus and rotatores) using ultrasound imaging are described and normal data provided on size, shape and symmetry of these muscles from a sample of 99 healthy subjects (46 males aged 20–72 years and 53 females aged 18–70 years). Significant gender differences were found (Po0:001) but muscle size did not alter significantly with age. Between-side symmetry can be used to assess abnormality of the deep neck muscle group but not semispinalis capitis. A regression equation is provided for predicting the cross-sectional area (CSA) of the deep neck muscles from spinous process length in males. Clinically, linear measurements can be used to predict the neck muscle CSAs (r ¼ 0:6620:84; Po0:001). The method described for assessing the neck muscles is a potentially valuable tool in clinical practice. r 2004 Elsevier Ltd. All rights reserved. Keywords: Ultrasonography; Muscle size; Neck muscles

1. Introduction Measurement of muscle size from ultrasound images can provide an objective assessment of muscle atrophy and hypertrophy (see Hides et al., 1995 and Stokes et al., 1997 for reviews). Pain, underlying pathology or injury and muscle inhibition, as well as individual muscles being part of a functional group, can prevent the assessment of muscle strength. Muscle size can provide an indirect measure of strength, as found in the neck Corresponding author. Research & Clinical Effectiveness Unit, Chartered Society of Physiotherapy, 14 Bedford Row, London WC1R 4ED, UK. Tel.: +44 20 7306 6601; fax: +44 20 7306 6653. E-mail address: [email protected] (G. Rankin).

1356-689X/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2004.08.004

extensors (Mayoux–Benhamou et al., 1989; Rezasoltani et al., 2002). It has also been demonstrated that resisted neck extension exercises significantly increase the strength and cross-sectional area (CSA) of the main neck extensors (Conley et al., 1997). The cross-sectional shape of various muscles has been characterized using shape ratios based on the muscle’s linear dimensions e.g. lumbar and cervical paraspinal muscles (Hides et al., 1992; Rezasoltani et al., 2002). Two posterior neck muscles have previously been measured using ultrasound imaging, splenius capitis (Reza Soltani et al., 1996) and semispinalis capitis (Rezasoltani et al., 1998). While the posterior neck muscles are easily accessible for ultrasound imaging, no study had investigated the deep posterior neck muscles,

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i.e. semispinalis cervicis, multifidus and rotatores when the present study was undertaken. Recently Kristjansson (2004) has produced data on multifidus. To assess a given muscle it is essential to know the normal values for that specific muscle. Previous ultrasound studies of the neck muscles provided normal data in relatively small numbers of normal subjects (Reza Soltani et al., 1996; Rezasoltani et al., 1998; Kristjansson, 2004). There is a need to expand normal databases and to include males and females from a wider range of ages, as recently reported for the lumbar multifidus muscle (Stokes et al., 2004). A relationship between muscle size and anthropometric variables potentially provides a simple method of predicting normal muscle sizes and gender differences have been found (Rezasoltani et al., 1998). The aims of the present study of the posterior neck muscles were to: i. Provide normal reference ranges for size, shape and symmetry in a large sample of males and females encompassing a wide age range. ii. Examine whether linear measurements relate closely enough with CSA to provide a rapid and simple means of assessing muscle size iii. Examine the relationship between muscle size and body mass, body mass index (BMI) and local anthropometric variables.

2. Methods 2.1. Subjects Muscles were scanned in 99 subjects, 46 males (aged 20–72 years) and 53 females (18–70 years). Demographic details are shown in Table 1. Subjects were either sedentary or moderately active. Sedentary subjects were defined as having occupations involving light or no manual work and not taking part in sports. Those moderately active were in occupations Table 1 Demographic details of subjects. Males were significantly older, taller, heavier and had greater body mass index (BMI) than females n

Age (years) Height (m) Body mass (kg) BMI (kg/m2)

Males 46

Females 53

Mean

SD

Mean

SD

41.6 1.77 83.8 26.7

14.1 0.07 12.0 3.3

34.9* 1.65*** 64.7*** 23.8***

14.1 0.06 9.5 3.5

n=number of subjects, SD=standard deviation. Significant differences between males and females: ***Po0:001; *Po0:05:

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involving moderate manual work but not heavy labour, and/or partaking in recreational sports up to four times a week, not competitively above club level. Exclusion criteria were a history of neurological, neuromuscular, rheumatological or systemic disease; current pregnancy; medication which might affect muscle size; any skin condition or wound in the area to be scanned; any history of neck pain of a severity to interfere with activities of daily living or require treatment; cervical spine fracture or surgery or any known spinal abnormality. The project was approved by the local Ethics Committees. Written informed consent was obtained from all subjects. 2.2. Procedure of ultrasound scanning An ALOKA SSD 1200 ultrasound scanner was used with a 5MHz convex (50 mm footprint) transducer and a 7.5 MHz linear array (80 mm footprint) transducer, (Aloka Co. Ltd, Tokyo, Japan). Images were captured, stored and measured using an ultrasound image analysis system (Department of Medical Physics and BioEngineering, St George’s Medical School, London), consisting of computer software, a National Instruments PCI-1408 analogue frame grabber and a pentium-based PCA running Windows 95. The software enabled offline analysis, using on-screen calipers to measure muscle dimensions and CSA (by tracing around the muscle border). The subject lay prone with the forehead resting just above the breathing hole in the plinth and the head in the midline, with their arms supported on the plinth’s armrests. The head and neck were positioned in neutral and the superficial posterior neck muscles were palpated lateral to the spinous processes from C2 to C7 to ensure that they were relaxed. The spinous processes of C2, C3 and C7 were palpated and marked on the skin with a chinagraph pencil. The spinous process of C3 was the scanning level, to enable a direct comparison with the data of Rezasoltani et al. (1998). 2.3. Anatomy of the posterior neck muscles The muscles are commonly described in four layers; the most superficial layer being trapezius and the second layer splenius capitis and cervicis (Fig. 1). The third layer consists of semispinalis capitis and cervicis (Takebe et al., 1974; Mayoux–Benhamou et al., 1989), and longissimus capitis is sometimes included (Reza Soltani et al., 1996). In a later study, Mayoux–Benhamou et al. (1997) placed semispinalis cervicis in the deepest (forth) layer, which has also been described as consisting of just the suboccipital muscles (Takebe et al., 1974), and others included multifidus

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Fig. 1. Magnetic resonance image showing a cross-section of the posterior cervical muscles. The CSA of semispinalis capitis (SEC) and the deep posterior cervical muscles (SCM) can be seen. Trapezius (T), Splenius capitis (SC), Levator scapulae (LS), Longissimus capitis and cervicis (LSC), Scalenus medius and anterior (SMA) and Sternocleidomastoid (SM) are marked on the diagram. Reproduced by kind permission of Springer-Verlag. Conley MS, Stone MH, Nimmons M, Dudley GA 1997 Specificity of resistance training resposes in neck muscle size and strength. European Journal of Applied Physiology 75: 445 Fig. 1.

(Mayoux–Benhamou et al., 1989) and rotatores (Reza Soltani et al., 1996). 2.4. Deep posterior neck muscles These comprise semispinalis cervicis, multifidus and rotatores. This group of muscles has a distinctive teardrop shape in cross-section. The fascial division between multifidus and semispinalis cervicis could not be identified consistently in all subjects and rotatores could not be identified from multifidus. Therefore, measurements were taken of the whole muscle group rather than the individual muscles. A 5 MHz convex transducer was placed transversely in the midline over C3 and the spinous process and laminae were identified. A central image was obtained for the measurement of spinous process length (Fig. 2). In some cases the left and right deep extensor muscles could be seen clearly on the central image (Fig. 2). If not, the transducer was moved laterally to each side to image the muscles bilaterally. The vertebral laminae were used as a consistent landmark to identify the deep border of the muscles. 2.5. Semispinalis capitis Rezasoltani et al. (1998) described the muscle as being divided into two sections by an aponeurotic intersection (Fig. 3). The procedure described by Rezasoltani et al. (1998) was followed, using a 7.5 MHz linear transducer placed transversely in the midline over C3, and the spinous process and laminae identified. It was then moved laterally to image the left and right muscles. The echogenic vertebral laminae and fascia dividing the muscle layers were identified. The transducer was slightly angled in cranial and caudad directions until the sharpest image of the bone and fascia was obtained.

Fig. 2. Ultrasound images showing the CSA of the left and right deep posterior neck muscles. The length of the spinous process is marked on the top scan; the CSA is marked on the left and linear dimensions on the right muscle in the bottom image. The linear dimensions are the greatest lateral dimension (L) and the greatest anteroposterior dimension (AP) perpendicular to the lateral dimension. Divisions on the vertical scale equivalent to 1 cm.

2.6. Measurements 2.6.1. Muscles The left and right CSA (cm2) of the deep posterior neck muscles and semispinalis capitis were measured. Two linear measurements (cm) of the muscles were made, defined as the greatest width (lateral (lat) dimension) of the muscle and the greatest depth (anteroposterior (AP) dimension) lying perpendicular to the lateral dimension (Figs. 2 and 3). Two scans were

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2.8. Anthropometric variables The spinous process length (cm) was measured from the central ultrasound image (Fig. 2). Neck length (distance from C2 to C7 spinous process) and three head dimensions—(i) AP; from the bridge of the nose to the base of the occiput, (ii) laterally over the top of the head between the ears and (iii) head circumference were also measured. 2.9. Data analysis

Fig. 3. Ultrasound image of the CSA of the left semispinalis capitis. The linear dimensions (L=lateral, AP=anteroposterior) are marked on the top scan. The CSA and the aponeurosis (A) dividing the muscle into medial and lateral parts are marked on the bottom image. Divisions on the vertical scale equivalent to 0.5 cm.

taken of each muscle and the mean of their measurements was used in all statistical analyses. Measurements were recorded to one decimal place. 2.7. Reliability of the ultrasound procedure Ten normal subjects (five males) were selected to provide reliability data for a wide range of ages (27–58 years), height (1.49–1.82 m), weight (58.8–89.9 kg) and BMI (24.1–33.4 kg/m2). The cervical muscles at C3 on the left side were scanned on two occasions, one week apart, at the same time of day by the lead investigator (GR). On each day, two images were taken to establish between-scans reliability. The repeatability of CSA measurements was high, with intraclass correlation coefficients (ICC) for between-scans and between-days being 0.98–0.99 for the deep muscle group and 0.99 for semispinalis capitis. Bland and Altman tests produced values of d that were close to zero and SDdiff values were very low. The 95% limits of agreement showed that measurements were repeatable between days to within 0.4 cm2 for the deep neck muscles and 0.16 cm2 for semispinalis capitis. Inter-rater reliability between two of the authors (GR and MS) was previously shown to be high for scanning the anterior tibial muscles: ICC=0.92 (Rankin and Stokes, 1998).

Gender differences in demographic details were compared using independent sample t tests. Muscle shape was described using a shape ratio defined as the lateral dimension divided by the AP dimension (Lat/AP). Data for muscle size and shape were expressed as means and standard deviations (SD), and males and females compared using independent sample t tests. There were no significant differences in size and shape data between the right and left sides, therefore, the mean of the data for the two sides was used in all calculations. Ranges for 95% of the sample population were calculated as the mean72SD. Males were subdivided into five age bands: 20–29 years (n ¼ 11), 30–39 years (n ¼ 13), 40–9 years (n ¼ 6), 50–59 years (n ¼ 10) and 60–72 years (n ¼ 6), and females four: 18–29 years (n ¼ 27), 30–39 years (n ¼ 9), 40–49 years (n ¼ 6) and 50–70 years (n ¼ 11). Muscle size and shape between different age groups were compared using one-way ANOVA. The relationships between CSA and linear dimensions, age and anthropometric variables were examined using Pearson’s correlation coefficient and linear regression analysis. Predictive regression equations, for estimating CSA from linear dimensions and anthropometric measures, were calculated. The difference between sides was calculated by dividing the value from the larger side by the smaller value and expressed as a percentage (% difference= [(larger/smaller side)  100]100). Mean and SD values were calculated for symmetry of muscle size and shape. Statistical analyses were performed using SPSS 9.0 for Windows software.

3. Results Muscle size, shape, symmetry and linear dimensions are shown in Table 2. 3.1. Muscle size 3.1.1. Gender effect The CSAs were significantly larger in males (Po0:001), but not when muscle size was normalized

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Table 2 Size, shape and symmetry of the deep posterior neck muscles and semispinalis capitis Males (n ¼ 46) Mean (SD) Deep posterior muscles CSA (cm2) Shape ratio (lat/AP) Lateral dimension (cm) Thickness (cm) Normalised size (cm2/kg) Symmetry (% difference between sides) Semispinalis capitis CSA (cm2) Shape ratio (lat/AP) Lateral dimension (cm) Thickness (cm) Normalized size (cm2/kg) Symmetry (% difference between sides)

Females (n ¼ 53) 95% range

Mean (SD)

95% range

P value

3.15 0.57 1.57 2.76 0.04 7.39

(0.67) (0.06) (0.17) (0.36) (0.01) (7.56)

1.81–4.48 0.45–0.70 1.22–1.91 2.05–3.48 — 0–22.51

2.60 0.57 1.40 2.49 0.04 8.41

(0.50) (0.10) (0.19) (0.28) (0.01) (6.95)

1.61–3.60 0.37–0.77 1.02–1.78 1.92–3.05 — 0–22.31

o0.0001 0.9727 o0.0001 o0.0001 0.2085 0.4871

1.77 7.20 3.73 0.53 0.02 12.62

(0.40) (1.14) (0.39) (0.08) (0.01) (11.64)

0.97–2.56 4.93–9.48 2.95–4.50 0.38–0.68 — 0–35.9

1.34 7.10 3.27 0.48 0.02 12.11

(0.42) (1.34) (0.48) (0.11) (0.01) (13.02)

0.49–2.19 4.42–9.79 2.31–4.24 0.26–0.70 — 0–75.90

o0.0001 0.6885 o0.0001 0.0110 0.5702 0.8397

n=number of subjects. SD=standard deviation. CSA=cross-sectional area. P values are for differences between males and females.

for body weight (Table 2). Similarly, there were highly significant gender differences in all linear dimensions (Po0:001) other than the thickness of semispinalis capitis, which was still significant (Po0:05). Table 1 shows that males were significantly older, taller, heavier and had greater BMI; males and females were therefore treated as separate groups in all analyses. 3.1.2. Effect of age There was no significant correlation between muscle CSA and age (r ¼ 0:0420:23). When subjects were subdivided into age bands there were no significant differences in muscle size between the different age groups (P values=0.08–0.40). 3.2. Muscle shape The deep muscles were teardrop shaped, the lateral dimension being approximately half the AP dimension (Fig. 2). Semispinalis capitis was wide and thin; its width being approximately seven times that of its thickness (Fig. 3). There were no gender effects on muscle shape ratios (Table 2). 3.3. Symmetry of muscle size and shape Symmetry was greater in the deep muscles than in semispinalis capitis (Table 2). There were no significant gender or age effects in the degree of symmetry. Asymmetry of shape ratio was high for semispinalis capitis, which was greater in females (Po0:05). The SD values for symmetry of size and shape were large, indicating considerable variation between subjects.

3.4. Correlations between muscle CSA and linear dimensions There were significant correlations (Po0:001) between CSA and linear dimensions; the highest being for the combined linear dimensions (lat  AP; Table 3). Regression equations for the prediction of CSA from the combined dimensions are shown in Table 3. 3.5. Correlations between muscle CSA and anthropometry There was a significant correlation between the CSA of the deep posterior neck muscles and spinous process length, being greater in males (r ¼ 0:79; Po0:001) compared to females (r ¼ 0:30; Po0:01). The linear relationship in males is shown in Fig. 4. The CSA of the left or right deep neck muscles in males can be predicted using the following regression equation: CSA=(1.61  spinous process length)1.42. There were other statistically significant correlations between muscle CSA and anthropometry in females, but coefficients were too low to be of clinical relevance (r ¼ 0:3020:44).

4. Discussion The present study has provided normal reference ranges for the size and shape of the deep posterior neck and semispinalis capitis muscles, a protocol for scanning and measuring these muscles has been presented.

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Table 3 Correlation between neck muscle cross-sectional area (CSA) and linear measurements and regression equations for predicting CSA from linear dimensions Dimensions

Males Regression equation

Deep posterior neck muscles (CSA) Combined 0.66  combined+0.25 Lateral (Lat) 3.29  lat2.01 Thickness (AP) 1.66  AP1.44 Semispinalis capitis (CSA) Combined 0.86  combined+0.07 Lateral (Lat) 0.78  lat1.13 Thickness (AP) 3.29  AP+0.03

r

Females Regression equation

r

0.96*** 0.85*** 0.89***

0.61  combined+0.47 0.19  lat+0.19 1.16  AP0.28

0.84*** 0.66*** 0.66***

0.86*** 0.76*** 0.63***

0.66  combined+0.29 0.69  lat0.92 2.79  AP+0.004

0.84*** 0.79*** 0.71***

r=correlation coefficient. Combined=lateral dimension  thickness. AP=anterior-posterior linear dimension=thickness. ***Po0:001:

5.0

CSA (cm2)

4.0

3.0

2.0

1.0 2.0

2.5 3.0 Spinous process length (cm)

3.5

Fig. 4. Graph showing the linear relationship between the CSA of the deep posterior neck muscles and spinous process length in males. The regression line and 95% prediction intervals are shown.

4.1. Muscle size The mean CSA values of semispinalis capitis found in this study were similar to those previously reported in 46 subjects aged 19–34 years (Rezasoltani et al., 1998).

Although not the only factor, muscle atrophy with ageing may be due to decreased physical activity (Harridge & Young, 1998). This may not have such a marked effect on the neck muscles, which need to support and move the head, regardless of activity level or age. This hypothesis is supported in a study by Boyd–Clark et al. (2002) who found that muscle spindle distribution, morphology and density in longus colli and multifidus did not change with age. They concluded that these muscles retain their functional capacity with ageing. However, there is evidence to suggest that muscle tissue in older subjects is partly replaced by fat and connective tissue (Parkkola et al., 1993; Tsubahara et al., 1995). On ultrasound images, muscle tissue appears relatively black because it only reflects small amounts of the ultrasound beam; this is termed low echogenicity. In contrast, connective tissue and bone show high echogenicity and appear white. Infiltration with fatty or fibrous tissue may increase the echogenicity of muscle tissue, making it appear ‘whiter’ but a reliable method of quantifying the degree of echogenicity on ultrasound images has yet to be developed. 4.2. Muscle shape

4.1.1. Gender effect Males had significantly larger neck muscles but not when normalized for body mass. Although this might suggest a close relationship between neck muscle size and body mass, correlations were low. Until more is understood about gender differences in neck muscle size, it is suggested that data for males and females are treated separately. 4.1.2. Effect of age An unexpected finding was that muscle size did not significantly alter with age. Previous studies have concentrated on limb muscles and shown a decrease in muscle size with increasing age (reviewed by McComas, 1996).

Distinctive shapes for both semispinalis capitis and the deep neck muscles assist identification of the muscles on ultrasound images. Change in muscle shape may occur with atrophy, hypertrophy or pathology but this requires investigation and the clinical relevance of muscle shape is not yet known. 4.3. Symmetry of muscle size The deep posterior muscles were more symmetrical than semispinalis capitis, which may reflect different functions of the muscles. Symmetry of the deep neck

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muscle group (mean difference =8.5%; range 0–22.5%) compares favourably with results for lumbar multifidus (Stokes et al., 2004) and other muscles in normal subjects (Stokes et al., 1997). Marked asymmetry may indicate pathology. In people with acute, unilateral low back pain, Hides et al. (1994) reported marked asymmetry of multifidus CSA at one vertebral level (between-side difference 3178%). The present findings suggest that if similar muscle size changes occur with pathology in the neck as for the lumbar spine, measurement of between-side differences may detect abnormality in the deep neck muscles but less so for semispinalis capitis. 4.4. Correlations between muscle CSA and anthropometry It is difficult to explain the gender difference in the ability to predict the CSA of the deep neck muscles from spinous process length but it perhaps reflects a difference in anatomy or function. 4.5. Methodological considerations 4.5.1. Scanning level Normal data have been provided for the C3 vertebral level. Further research is needed to obtain data for the neck muscles at all relevant vertebral levels and to investigate the relationship between muscle size at different levels. This has been studied in lumbar multifidus where CSA at L4 and L5 were found to be predictive of one another (Stokes et al., 2004). The relationship between muscle size and anthropometric measures also requires further investigation at different levels. 4.5.2. Measurement of individual neck muscles The main function of semispinalis capitis, cervicis and multifidus has been shown to be neck extension (Takebe et al., 1974; Conley et al., 1995; Mayoux-Benhamou et al., 1997). It is unclear whether these muscles are active (Mayoux-Benhamou et al., 1997) or inactive (Takebe et al., 1974) at rest. There is evidence that lumbar multifidus has an important stability function (Bogduk et al., 1992; Cholewicki and McGill 1996). Little is known about the deep posterior muscles in the cervical spine but there may be good reason to measure multifidus separately from the other muscles. In the present study it was not possible to differentiate the muscle borders in all subjects. A recent study investigated the reliability of ultrasonography for measuring the size of cervical multifidus in asymptomatic (n ¼ 10) and symptomatic (chronic whiplash associated disorder; n ¼ 10) subjects

(Kristjansson, 2004). Measurements were taken at C4 which was found to be the vertebral level where the configuration of multifidus was clearest. Good intratester agreement was found in both groups. Inter-tester reliability was good in the asymptomatic but questionable in the symptomatic group. Cervical multifidus size was significantly reduced in the symptomatic subjects and this was associated with a lack of clarity of the facial layer dividing multifidus and semispinalis cervicis, reducing the reliability of measurements. Kristjansson (2004) suggested that shrinkage of the fascial layer obscured its outlines and that this may be a diagnostic sign of muscle atrophy. This requires further investigation but current evidence suggests that the most robust approach is to measure the total size of the deep muscle group, noting the clarity of the fascial layers and echogenicity of the muscle tissue, and, where possible, measuring multifidus individually. 4.5.3. Correlations between muscle CSA and linear dimensions Some scanners only allow linear measurements to be taken on-line and in practical terms linear measurements are quicker and require less skill. The present study has established a strong relationship between combined linear dimensions and CSA and regression equations for this relationship have been provided for normal subject for clinical use. The relationship needs to be established in patients with muscle wasting. 4.6. Clinical applications of ultrasound imaging of the neck muscles These measurements, taken as part of the patient’s assessment, provide reliable objective data of muscle size/strength and also useful evidence for the clinical reasoning process adopted by expert clinicians (Jones, 1995). Further research may establish the benefits of ultrasound imaging of these muscles in identifying muscle atrophy, assessing the effects of interventions and as a biofeedback tool but in the meantime, clinicians with access to ultrasound equipment are encouraged to use and develop the procedures and assessment techniques described in this paper. Physiotherapists adopting ultrasound imaging are advised to follow the guidelines of the British Medical Ultrasound Society (website: www.bmus.org), to ensure the technique is used appropriately.

5. Conclusions Procedures for ultrasound imaging and measurement of the posterior neck muscles at the C3 level have been described. Normal data for size, shape and symmetry of

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the muscles have been presented for males and females of different ages. Between-side symmetry can be used to assess abnormality of the deep neck muscle group but not semispinalis capitis. The correlation analyses between muscle size and anthropometric measures produced only one useful regression equation, which was for predicting CSA of the deep neck muscles from spinous process length in males. Combined linear measurements reflected CSA accurately enough to be used for more rapid and simple assessment of muscle size in normal subjects but the robustness of linear measurements needs to be established for clinical use in patients with atrophy.

Acknowledgements The authors thank the subjects who took part in the study, the Neuro-disability Research Trust for financial support, and Dr Anthony Swan for statistical support. References Bogduk N, Macintosh JE, Pearcy MJ. A universal model of the lumbar back muscles in the upright position. Spine 1992;17:897–913. Boyd-Clark LC, Briggs CS, Galea MP. Muscle spindle distribution, morphology, and density in longus colli and multifidus muscles of the cervical spine. Spine 2002;27:694–701. Cholewicki J, McGill SM. Mechanical stability of the in vivo lumbar spine: implications for injury and chronic low back pain. Clinical Biomechanics 1996;11:1–15. Conley MS, Meyer RA, Bloomberg JJ, Feeback DL, Dudley GA. Non-invasive analysis of human neck muscle function. Spine 1995;20:2505–12. Conley MS, Stone MH, Nimmons M, Dudley GA. Specificity of resistance training resposes in neck muscle size and strength. European Journal of Applied Physiology 1997;75:443–8. Harridge SDR, Young A. Skeletal muscle. In: Pathy MSJ editor. Principles and practice of geriatric medicine. 3rd edn. Wiley: Chichester; 1998. p. 897–905. Hides JA, Cooper DH, Stokes MJ. Diagnostic ultrasound imaging for measurement of the lumbar multifidus muscle in normal young adults. Physiotherapy Theory and Practice 1992;8:19–26.

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Hides JA, Stokes MJ, Saide M, Jull GA, Cooper DH. Evidence of lumbar multifidus muscle wasting ipsilateral to symptoms in patients with acute/subacute low back pain. Spine 1994;19:165–72. Hides J, Richardson C, Jull G, Davies SE. Ultrasound imaging in rehabilitation. Australian Journal of Physiotherapy 1995;41: 187–93. Jones M. Clinical reasoning and pain. Manual Therapy 1995;1:17–24. Kristjansson E. Reliability of ultrasonography for the cervical multifidus muscle in asymptomatic and symptomatic subjects. Manual Therapy 2004;9:83–8. Mayoux-Benhamou MA, Wybier M, Revel M. Strength and crosssectional area of the dorsal neck muscles. Ergonomics 1989;32: 513–8. Mayoux-Benhamou MA, Revel M, Vallee C. Selective electromyography of dorsal neck muscles in humans. Experimental Brain Research 1997;113:353–60. McComas AJ. Skeletal muscle. Human Kinetics, USA: Form and function; 1996. Parkkola R, Ryto¨koski U, Kormano M. Magnetic resonance imaging of the discs and trunk muscles in patients with chronic low back pain and healthy control subjects. Spine 1993;18:830–6. Rankin G, Stokes. Reliability of assessment tools in rehabilitation: an illustration of appropriate statistical analysis. Clinical Rehabilitation 1998;12:187–99. Reza Soltani A, Kallinen M, Ma¨lkia¨ E, Vihko V. Ultrasonography of the neck splenius capitis muscle. Acta Radiologica 1996;37:647–50. Rezasoltani A, Kallinen M, Ma¨lkia¨ E, Vihko V. Neck semispinalis capitis muscle size in sitting and prone positions measured by realtime ultrasonography. Clinical Rehabilitation 1998;12:36–44. Rezasoltani A, Ylinen J, Vihko V. Isometric cervical extension force and dimensions of semispinalis capitis muscle. Journal of Rehabilitation Research and Development 2002;39:423–8. Stokes M, Hides J, Nassiri DK. Musculoskeletal ultrasound imaging: diagnostic and treatment aid in rehabilitation. Physical Therapy Reviews 1997;2:73–92. Stokes M, Rankin G, Newham DJ. Ultrasound imaging of lumbar multifidus muscle: normal reference ranges for measurements and practical guidance on the technique. Manual Therapy 2004, doi:10.1016/j.math.2004.08.013. Takebe K, Vitti M, Basmajian JV. The functions of semispinalis capitis and splenius capitis muscles: an electromyographic study. Anatatomical Records 1974;179:477–80. Tsubahara A, Chino N, Akaboshi K, Okajima Y, Takahashi H. Agerelated changes of water and fat content in muscles estimated by magnetic resonance (MR) imaging. Disability and Rehabilitation 1995;17:298–304.

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Manual Therapy 10 (2005) 116–126 www.elsevier.com/locate/math

Original article

Ultrasound imaging of lumbar multifidus muscle: normal reference ranges for measurements and practical guidance on the technique M. Stokesa,c,, G. Rankina, D.J. Newhamb a

Institute of Complex Neuro-disability, Royal Hospital for Neuro-disability, London, UK b Centre for Applied Biomedical Research, King’s College London, UK c School of Health Professions and Rehabilitation Sciences, University of Southampton, Highfield Campus, Southampton, Hants SO17 1BJ,UK

Abstract This cross-sectional, prospective study aimed to produce normal reference data for measurements of the lumbar multifidus muscle. A total of 120 subjects, 68 females (aged 20–64 years) and 52 males (20–69 years) were studied. Bilateral transverse ultrasound images were made of multifidus at the fourth and fifth lumbar vertebrae (L4 & L5). Cross-sectional area (CSA, cm2) and linear dimensions (AP, anteroposterior; Lat, lateral) were measured and the latter expressed as a ratio (AP/Lat) to reflect shape. Relationships between CSA and anthropometric measures were examined. Multifidus CSA was larger in males (Po0.001) and age had no effect. The CSA was larger at L5 than L4 (Po0.001) and highly correlated between the two levels (males r=0.82, females 0.80). Differences in muscle shape were observed for gender, age and vertebral level. Between-side symmetry was high for size but not shape (CSA o10% difference). Linear measurements multiplied (AP  Lat) correlated highly with CSA (all groups rX0.94, Po0.0001). The AP dimension was also acceptably predictive of CSA at L4 (rX0.79). There were no clinically useful correlations between CSA and anthropometric measures. These findings provide normal references ranges for objective assessment of lumbar multifidus. This paper also addresses specific practical issues when scanning multifidus. r 2004 Elsevier Ltd. All rights reserved.

1. Introduction Ultrasound imaging of the lumbar multifidus muscle is of increasing interest to physiotherapists, both for clinical and research purposes. Clinically, the application is twofold: as an objective assessment tool for detecting abnormalities and monitoring changes during recovery (Hides et al., 1994, 1996); and for visual biofeedback during re-education of muscle contraction (Hides et al., 1998). The characteristics of multifidus for which normal data are available include cross-sectional area (CSA), linear measurements and shape, in small and relatively young populations (Hides et al., 1992, 1994). Corresponding author. Chair in Neuromuscular Rehabilitation, School of Health Professions and Rehabilitation Sciences, University of Southampton, Highfield Campus, Southampton, Hants SO17 1BJ,UK. E-mail address: [email protected] (M. Stokes).

1356-689X/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2004.08.013

Measurement of muscle size using ultrasound has provided an accurate assessment of muscle wasting in various muscles (see Stokes et al., 1997 for review). In acute low back pain (LBP), severe atrophy of multifidus was found to be selective and confined to the vertebral level and side of pain symptoms (Hides et al., 1994). The technique was also useful in demonstrating that multifidus size does not recover when pain subsides unless it undergoes specific exercises (Hides et al., 1996). For the technique to be applicable to populations other than those studied previously, normal data are required for subjects over a wider age range. Of the various skeletal muscles explored with ultrasound scanning (see Stokes et al., 1997 for a review), lumbar multifidus is one of the most difficult to image and interpret. This is mainly because its lateral border with longissimus (an erector spinae muscle) is often not clear enough to see without refinements in the procedure.

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When imaging multifidus, it is important to understand its functional anatomy, the main feature of which is the segmental arrangement of its fibres (Bogduk, 1997; Bogduk et al., 1992; Macintosh et al., 1986). Multifidus has both movement and stabilising roles. Working bilaterally with the other lumbar muscles, multifidus produces extension of the lumbar spine (Bogduk et al., 1992) and acts as a stabilizer in rotation, counterbalancing the flexion force produced simultaneously with rotation by the oblique abdominal muscles (Bogduk, 1997). Knowledge of this functional anatomy assists in imaging the muscle and using various manoeuvres for biofeedback. The present study examined multifidus size and shape in normal subjects, and sought predictive equations for estimating the expected size. The paper also provides practical details of the imaging technique to help obtain and interpret scans. Aims 1. To provide reference ranges for multifidus size and shape at vertebral levels L4 and L5 in normal males and females over a wide age range. 2. To investigate the degree of symmetry of multifidus size and shape. 3. To examine the relationship between multifidus size and various anthropometric variables to provide predictive equations for muscle size.

2. Methods Real-time ultrasound images of lumbar multifidus were taken bilaterally at vertebral levels L4 and L5. 2.1. Subjects A total of 120 subjects, 68 females (aged 20–64 years) and 52 males (aged 20–69 years), were studied (see Table 1 for demographic details). The discrepancy in numbers of subjects studied at the two vertebral levels was due to initial subjects only being scanned at L4. Subjects were either sedentary or moderately active. Sedentary subjects were in occupations involving light or no manual work and did not take part in sports. Those moderately active were in occupations involving moderate manual work but no heavy labour and/or taking part in recreational sports up to four times a week but not competitively above club level. Exclusion criteria were a history of neurological, neuromuscular, rheumatological or systemic disease; pregnancy, medication which might affect muscle size; any skin condition or wound in the area to be scanned; a lifetime history of low back pain of a severity to interfere with activities of daily living or require treatment; lifetime history of spinal or pelvic fractures, lumbar

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surgery or any known spinal abnormality, such as scoliosis or spondylolithesis. The project received ethics approval from the Riverside Research Ethics Committee and King’s College London Research Ethics Committee. Written informed consent was obtained from subjects. 2.2. Procedure of ultrasound scanning The subject lay prone with the forehead resting just above the breathing hole in the plinth, the head in the midline and the arms supported on the plinth’s armrests. One or two pillows were placed under the hips to eliminate the lumbar lordosis. The spinous processes were palpated and marked with a chinagraph pencil. The spinous process of L5 was identified by palpating cranially from the sacrum. It is a deep, small, blunted bony point lying at the centre of the lumbosacral depression. The spinous process of L4, which is described as a comparatively large and sagitally ridged eminence (Grieve 1983), was identified by palpating cranially from L5. An Aloka SSD 1200 ultrasound scanner was used with a 5 Mz convex (50 mm footprint) transducer (Aloka Co. Ltd, Mitaka-shi, Tokyo, Japan). The transducer was first placed longitudinally over the lower lumbar spine, in the mid-line, to orientate and confirm the marks on the skin. This produced a scan of the spinous processes, which resembled the ‘Loch Ness Monster’ (as described by Nelmarı´ van Huyssteen MCSP, personal communication, with permission), seen in Fig. 1. The transducer was then rotated through 901 to lie transversely in the midline and the spinous processes and laminae were identified on a cross-sectional scan (Fig. 2). The transducer was then moved laterally to each side to image the left and right multifidus muscles (see Fig. 3 for L4 and Fig. 4 for L5). The echogenic vertebral laminae were used as a consistent landmark to identify the deep border of the muscle. In cases where it was difficult to clearly distinguish the lateral border of multifidus from longissimus, the subject was asked to contract the muscle by slightly raising the leg on the ipsilateral side and then relaxing before the image was taken. Images were captured, stored and measured off-line using an ultrasound image and analysis system (Department of Medical Physics and Bio-Engineering, St George’s Hospital, Tooting, London), consisting of computer software, a National Instruments PCI-1408 analogue frame grabber and pentium-based PC running Windows 95. 2.2.1. Ultrasound measurements The cross-sectional area or CSA (cm2) of multifidus was measured by tracing around the inner edge of the

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118 Table 1 Demographic details of subjects n Vertebral Level L4 Males 52

Age (years) Height (m) Body mass (kg) BMI (kg/m2)

Vertebral Level L5 Females 68

Males 45

Females 46

Mean

SD

Mean

SD

Mean

SD

Mean

SD

40.1 1.78 82.8 25.8

13.0 0.06 11.0 3.2

34.2* 1.65*** 62.9*** 23.0***

12.8 0.06 8.9 3.1

39.0 1.77 82.5 25.7

13.0 0.06 10.4 2.9

31.6** 1.66*** 61.8*** 22.3***

11.7 0.06 7.2 2.2

Males were significantly older, taller, heavier and had greater body mass index (BMI) than females. n=number of subjects. Significant differences between males and females: ***Po0.001 **Po0.01 *Po0.05.

muscle border with the on-screen cursor. Two linear measurements were made, defined as the greatest depth (anteroposterior, AP) and the greatest width (lateral dimension), lying perpendicular to the AP dimension. Muscle shape was expressed as a ratio of the linear measurements, with the AP divided by the lateral dimension (AP/Lat), as described by Hides et al. (1992). The length (cm) of the spinous process (SPL) and horizontal distance (cm) between the lateral edge of each lamina (bilateral lamina width) were also measured to examine their relationships with CSA.

Fig. 1. Saggital (longitudinal) view of the lumbar spine. A central image over the spinous processes (SP) resembles the ‘Loch Ness Monster’. This image is used to orientate prior to transverse scanning or moving laterally to obtain a longitudinal image over multifidus for biofeedback (usually with a linear probe, as in Fig. 6). (5 MHz Linear probe.)

Fig. 2. Bilateral transverse scan at the level of the fourth lumbar vertebra (L4), showing the spinous process in the centre of the image and the echogenic laminae (L) appearing as bright white horizontal landmarks, either side of the base of the spinous process (SP) and beneath multifidus (M). (5 MHz curvilinear probe.)

2.2.2. Reliability of the ultrasound procedure Ten normal subjects (five males) were selected to provide reliability data for a wide range of ages (27–58 years), height (1.49–1.82 m), weight (58.8–89.9 kg) and BMI (24.1–33.4 kg/m2). Lumbar multifidus at L4 on the left side was scanned on two occasions, one week apart in a blinded fashion, at the same time of day by one operator (GR). On each day, two images were taken to establish between-scan reliability. To relocate the scanning sites accurately, the surface marking for L4 spinous process was traced onto a transparent sheet, together with bony landmarks and any permanent skin blemishes, such as freckles and scars. The CSA of multifidus, SPL and bilateral lamina width were measured. Data analysis included intraclass correlations (ICCs; Chinn, 1990; Riddle et al., 1989), and Bland and Altman tests (Bland and Altman, 1986). Muscle and anthropometric measurements were highly repeatable. The ICCs for multifidus CSA ranged between 0.98 and 1.00. Bland and Altman tests produced values of d that were close to zero and SDdiff values were very low. The 95% limits of agreement for between-scans reliability was approximately 0.25–0.5 cm2, whilst for between-days reliability 0.62–0.67 cm2.

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Fig. 4. Transverse scan of the right multifidus muscle at the fifth vertebral level (L5). The spinous process (SP) is shorter and the lateral edge less steep than at L4. (5 MHz curvilinear probe.)

anterior superior iliac spines (ASIS) was measured with the subject lying supine. 2.4. Analysis of data Differences in age, height, body mass and BMI were compared between males and females using independent sample t-tests.

Fig. 3. Transverse scans of the left multifidus muscle at the fourth vertebral level (L4). The round shape of the multifidus (M) muscle is clearly evident in (a) and is oval in (b). Multifidus is bordered by the lamina (L) and spinous process (SP) as indicated. The lateral border is marked by the abrupt ending of transverse fasciae of longissimus (Lo), in both cases. (5 MHz curvilinear probe.)

For L4 SPL and bilateral lamina width, ICCs ranged from 0.95 to 0.99 for between-scans and between-days. Inter-rater reliability between two of the authors (GR and MS) was previously shown to be high for scanning the anterior tibial muscles: ICC=0.92 (Rankin and Stokes, 1998).

2.4.1. Multifidus size and shape Data for multifidus size and shape were not significantly different between the right and left sides and so were averaged for each subject, and the means and SD calculated for each group. Results for males and females were compared using independent sample t tests, and for L4 and L5 using paired t tests. Subsequently, due to differences observed, data for males, females and the two vertebral levels were treated as four separate groups. The ranges of values of muscle CSA and shape (ratios described above) for 95% of the sample populations (mean+2SD) were calculated. Muscle size and shape in different age groups (detailed later) were compared using one-way ANOVA.

2.3. External anthropometric measurements

2.4.2. Degree of symmetry of multifidus size and shape The difference between sides was calculated by dividing the value from the larger side by the smaller value and expressed as a percentage (% difference= [(largest/smallest value)  100]–100). Means, SD and 95% ranges (mean72SD) for symmetry were calculated for both size and shape.

The distances (cm) between the spinous processes of C7 and L5, and between the posterior superior iliac spines (PSIS) were measured using a tape measure with the subject lying prone. The distance (cm) between the

2.4.3. Relationship between muscle area, linear and anthropometric measures The relationship between multifidus CSA and age, height, body mass, BMI and anthropometric variables

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were investigated using Pearson’s correlation coefficient, and stepwise linear regression analysis. The relationships between multifidus CSA and linear dimensions, and between CSA at L4 and L5 were examined using Pearson’s correlation coefficient and linear regression.

3. Results Multifidus CSA was significantly greater in males than females and also larger at L5 than at L4. Age had a significant effect on shape but not size. There were statistically significant correlations between CSA with SPL and lamina width but were not considered clinically significant to enable accurate prediction of multifidus size. High correlation between L4 and L5 CSA enables the size of one to be predicted from the other using regression equations. Linear measurements were more predictive of CSA at L4 than at L5 and the multiplied dimensions gave the best results. 3.1. Multifidus size The means, SD and reference ranges (95% of population studied) for multifidus size at L4 and L5 are presented separately for males and females in Table 2. 3.1.1. Effect of gender Males had significantly greater multifidus CSA (Po0.001) but when normalized for body mass, there was not a significant gender difference (Table 3). However, it can be seen in Table 1 that males were significantly older, taller, heavier and had greater BMIs, so the two groups were analysed separately. 3.1.2. Effect of age Multifidus CSA did not correlate significantly with age. There was no significant difference in size between different 10-year age bands, for either gender or for either vertebral level. There were, however, qualitative differences observed in terms of greater echogneicity with increasing age in some cases. 3.1.3. Effect of vertebral level The CSA was significantly larger (Po0.001) at L5 than L4, by a mean of 14% in males and 21% in females (Table 4). The gender difference in this effect of vertebral level was significant (Po0.05). There were high and significant (Po0.001) correlations between the CSA at L4 and L5 in both males (r=0.82) and females (r=0.80). Regression equations for predicting multifidus CSA at L4 and L5 are shown in Table 5.

Table 2 Multifidus size and shape at the fourth (L4) and fifth (L5) vertebral levels Males

Females

P-value

L4 n CSA (cm2) Mean SD 95% Reference range

52

68

7.87 1.85 4.24–11.50

5.55 1.28 3.03–8.06

0.000

Shape ratio Mean SD 95% Reference range

1.02 0.15 0.72–1.33

1.05 0.21 0.64–1.47

0.430

L5 n CSA (cm2) Mean SD 95% Reference range

45

46

8.91 1.68 5.62–12.20

6.65 1.00 4.69–8.60

0.000

Shape ratio Mean SD 95% Reference range

1.03 0.17 0.70–1.36

0.95 0.17 0.62–1.28

0.025

Males had significantly larger muscles than the females at both levels. n=number of subjects. CSA=cross-sectional area. P values for differences between males and females.

Table 3 Multifidus size normalized for body mass Males

Females

P-value

L4 Mean SD

0.10 0.02

0.09 0.02

0.140

L5 Mean SD

0.11 0.02

0.11 0.02

0.914

Values calculated by dividing muscle cross-sectional area (cm2) by body mass (kg).

3.2. Multifidus shape The results for shape ratios of multifidus in crosssection are presented in Table 2. Different shapes in terms of muscle outline were observed at L4, such as oval, round and triangular (see Fig. 5). 3.2.1. Effect of gender The AP and lateral dimensions were almost equal in males (shape ratio close to 1.0), at both vertebral levels. In females, this shape was similar to males at L4 but at L5, the lateral dimension was greater, giving a

ARTICLE IN PRESS M. Stokes et al. / Manual Therapy 10 (2005) 116–126 Table 4 Effect of vertebral level on multifidus size and shape CSA (cm2) L4

Shape Ratio

L5

%Difference

L4

L5

Males (n=44) Mean 7.97 SD 1.80

8.89***a 1.69

13.60 17.90

1.03 0.16

1.04 0.17

Females (n=45) Mean 5.55 SD 0.99

6.64***a 1.01

20.88*b 13.42

1.02 0.17

0.95***a 0.17

***Po0.001. *Po0.05. a Paired t-test using L4 and L5 differences. b Two group t-test comparing males and females.

Table 5 Regression equations for predicting multfidus size at L4 and L5 from one another Males

Females

L4 CSA=0.19+0.88  L5CSA L5 CSA=2.74+0.77  L4CSA

L4 CSA=0.30+0.79  L5CSA L5 CSA=2.11+0.82  L4CSA

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subdivided into age bands in Table 6. The youngest groups had the smallest shape ratios, with post hoc analysis revealing a consistent significant difference between the 20–29 year age group and those in the 30–39 and 40–49 year age groups. 3.2.3. Effect of vertebral level In females there was a significant (Po0.001) difference in shape ratio between vertebral levels L4 and L5, whilst no difference was found in males (Table 4). At L4 in females, the AP and lateral dimensions were almost equal (giving a round profile) and at L5 the lateral dimension was greater, giving a lower ratio (i.e. oval/flatter profile), as seen in Figs. 3 and 4, respectively. 3.3. Symmetry of multifidus size and shape Mean values for between-side differences in CSA for the four groups were between 7.2 and 9.6%, and for shape ratio 9.9–12.3% (Table 7). However, reference ranges and SDs were high, indicating large individual variation. There were no significant differences for symmetry between genders, age groups or vertebral levels. 3.4. Correlation between multifidus cross-sectional area and linear measurements Linear measurements were highly correlated with multifidus CSA and results for coefficients greater than 0.6 are shown in Table 8, together with predictive regression equations. The predictive value of the AP dimension was higher at L4 than at L5 and the best results (X0.94) were found when the linear measurements were combined i.e. multiplied (Table 8). 3.5. Correlations between multifidus size and anthropometry

Fig. 5. Triangular shape of multifidus at the fourth lumbar vertebral level (L4). The shape of this muscle suggests hypertrophy, as it was seen in some of the more physically active subjects. The different connective tissue patterns between multifidus and longissimus are evident. (5 MHz curvilinear probe.)

significantly smaller ratio than in males (mean shape ratio=0.95, Po0.05). 3.2.2. Effect of age There were significant differences in multifidus shape at L5 between age groups in both genders, who were

In both genders and at both vertebral levels, there were significant positive correlations (Po0.05–0.001) between CSA and spinous process length (r=0.38–0.60) and laminar width (r=0.36–0.52). There were no significant correlations between CSA with height, body mass or BMI, except in females at L4 there was a significant (Po0.05) but weak correlation with body mass (r=0.26). There were no significant correlations between multifidus size with the distance between C7 and L5, the ASISs or PSISs. The highest correlation coefficient was that for multifidus CSA and SPL at L4 in males (r=0.60; Po0.0001).

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Table 6 Shape ratios for multifidus at L4 and L5 in different age groups Age Band Group (Years)

1 20–29

2 30–39

3 40–49

4 50–69

Males L4 n Mean (SD) 95% range L5 n Mean (SD) 95% range

13 0.95(0.16) 0.63–1.27 13 0.89(0.11) 0.67–1.10

16 1.05(0.12) 0.81–1.30 14 1.03(0.11) 0.82–1.25

7 1.02(0.20) 0.63–1.42 4 1.22(0.26) 0.70–1.73

16 1.06(0.14) 0.77–1.34 14 1.12(0.14) 0.85–1.38

Females L4 n Mean (SD) 95% range L5 n Mean (SD) 95% range

35 1.01(0.23) 0.56–1.47 27 0.90(0.11) 0.68–1.12

11 1.03(0.17) 0.70–1.37 8 1.03(0.18) 0.68–1.39

11 1.15(0.21) 0.74–1.56 5 1.16(0.26) 0.65–1.67

11 1.10(0.16) 0.79–1.40 5 0.91(0.09) 0.74–1.08

P-values for differences between age groups (e.g. group 1 versus group 2) Males 1v2 1v3 L4 NS NS L5 0.0022 0.0019

1v4 NS 0.0001

2v3 NS 0.0484

2v4 NS NS

3v4 NS NS

Females L4 L5

NS NS

NS NS

NS NS

NS NS

NS 0.0124

NS 0.0005

n=number of subjects. SD=standard deviation. NS=not significant 40.05.

Table 7 Symmetry of multifidus size and shape for males and females at L4 and L5 Males

Females

% difference between sides

L4 (n=52)

L5 (n=45)

L4 (n=68)

L5 (n=46)

CSA Mean (SD) 95% range

9.6 (8.1) 0–25.9

8.1 (5.5) 0–19.0

7.2 (7.0) 0–21.2

7.2 (6.5) 0–20.1

Shape ratio Mean (SD) 95% range

10.7 (8.4) 0–27.5

9.9 (9.0) 0–27.9

12.3 (13.0) 0–38.3

12.2 (9.2) 0–30.6

There were no significant differences between genders or the two vertebral levels. CSA=cross-sectional area. 95% range=lower and upper limits of range of values for 95% of the sample population.

4. Discussion

4.1. Multifidus size

Reference ranges for multifidus size and shape were produced for normal subjects of different ages. Muscle size was influenced by gender and vertebral level but not age. The CSA can be estimated from the muscle’s linear measurements or the CSA of the muscle at the adjacent vertebral level. None of the anthropometric measures were predictive of muscle size.

4.1.1. Effect of gender The larger muscles in males were expected and appear to be due to differences in body mass. The mean CSA at L4 in females agreed with findings by Hides et al. (1992, 1994) but the mean size of almost 8 cm2 in males was larger than previously reported (6.2 cm2), perhaps due to the present males being heavier (mean mass 82.8 kg

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Table 8 Correlation between multifidus cross-sectional area (CSA) and linear measurements Dimensions

Males

Females

Regression equation

r

Regression equation

r

L4 CSA vs. Combined AP

0.84  (AP  Lat)+0.18 3.85  AP-3.78

0.96*** 0.80***

0.73  (AP  Lat)+0.72 2.73  AP-1.54

0.95*** 0.70***

L5 CSA vs. Combined AP

0.70  (AP  Lat)+0.63 2.93  AP-0.61

0.95*** 0.66***

0.69  (AP  Lat)+1.03 not applicable

0.94*** 0.54***

***Po0.0001. AP=anterior-posterior linear dimension, combined=AP multiplied by lateral dimension (AP  Lat), r=correlation coefficient.

versus 72.8 kg). Also, in the above studies of Hides et al., subjects were excluded if they took part in sports or fitness training involving the back muscles in the previous three months, whilst many of the present subjects were more active. Multifidus size at L5 has only been studied in young females and the mean CSA of 7.1 cm2 compares favourably with the present 6.6 cm2 (Hides et al., 1995). 4.1.2. Effect of age Age did not have a significant effect on multifidus size but the quality of the muscle may have altered. Changes in water and fat content occur with age and produce changes in signal intensity on MRI scans (Tsubahara et al., 1995). On ultrasound images, muscle tissue appears relatively black because it only reflects small amounts of the ultrasound beam; this is termed low echogenicity. In contrast, connective tissue and bone show high echogenicity and appear white. Infiltration with fatty or fibrous tissue may increase the echogenicity of muscle making it appear ‘whiter’, as observed in some of the present older subjects but a reliable method of quantifying these changes has yet to be developed. Further research is needed to fully evaluate changes that occur in multifidus with age and activity, in terms of the size and quality of the muscle. 4.1.3. Effect of vertebral level The greater size of multifidus at L5 than L4 agreed with Hides et al., (1995; L4 mean approx. 5 cm2, L5, 7 cm2). A cadaver study demonstrated that multifidus muscle bulk progressively increased from L2 caudally to S1 (Amonoo-Kuofi, 1983). An interesting finding was the high correlation between muscle size at the two levels, which is useful for predicting one from the other (see below). 4.2. Multifidus shape The shape ratio was only influenced by age at L5, with the value increasing with age, indicating that the muscle

became more ovoid in the AP direction. The mean shape ratio in the youngest group of males at L4 (0.95) agreed with that found in a similar group (0.91) by Hides et al. (1992). Multifidus shape is not always regular, particularly in subjects with relatively large muscles, which can appear more triangular than ovoid (see Fig. 5). The medial and inferior (deep) borders are confined by the spinous process and lamina, so multifidus can only hypertrophy in a lateral or superior (superficial) direction, which may explain the more triangular shape of hypertrophied muscles (see Fig. 5). In such cases, the shape ratio is misleading as it would tend to suggest a round shape. It may be more appropriate to describe a triangular shaped muscle using three measurements i.e the superior, medial and lateral borders. The clinical relevance of multifidus shape has yet to be explored but preliminary observations suggest that it may reflect changes in muscle tone. Subjects with acute LBP had a significantly rounder multifidus muscle at the affected level, possibly indicating muscle spasm (Hides et al., 1994), but this was not investigated formally. 4.3. Prediction of normal values and assessment of abnormality Assessment of abnormal multifidus size and shape can be made by comparison with the normal 95% reference ranges (Table 2) for similar populations, in terms of gender, age and activity level. The ability to predict the CSA of L4 and L5 from each other (Table 5) is potentially useful but dependent on one level being normal. In acute unilateral LBP, muscle wasting was found to be isolated to the affected segmental level (Hides et al., 1994) but this may not be the case for chronic LBP or other conditions affecting the paraspinal muscles. 4.3.1. Correlation between muscle area and linear measurements Linear measurements can be made quickly and easily, requiring less skill than that for tracing round the

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muscle border, and not all ultrasound scanners have a facility to measure area. Linear measurements are therefore more applicable for clinical use than CSA, provided they predict area accurately. The combined linear measurements (AP  Lat) were highly correlated with CSA at both vertebral levels and in both genders (Table 8). The present results for L4 and L5 (ranging from r=0.94 to 0.96) compare favourably with those found at L4 by Hides et al. (1992, males r=0.98, females 0.93; & 1994, males 0.97, females 0.92) in young healthy subjects. However, it is known that this correlation weakens when muscle becomes atrophied (Hides et al., 1994) and so cannot be assumed in all situations. The AP dimension was also highly correlated with area at L4 and could thus be used as a quick clinical measure to estimate area but the relationship at L5, although statistically significant, was not as strong. Multiplying the linear measurements provides similar two-dimensional values to area (cm2) and is obviously preferable to a single measurement if area cannot be measured. 4.3.2. Symmetry of multifidus size and shape Between-side comparisons are often used clinically to assess unilateral abnormalities. Symmetry of multifidus CSA (Table 7) was lower than in previous studies (Hides et al., 1992, 1994), possibly due to variation in the activity levels between study populations. If the higher degree of asymmetry was due to physical activity, it could be hypothesized that the dominant side would be larger. However, although 82% of males and 90% of females were right handed, there was no significant difference in CSA between sides and no trends of asymmetry related to handedness were seen. Subjects with acute LBP had much higher degrees of asymmetry (mean approximately 30%, range 15–46%; Hides et al., 1994) than the present subjects, despite the large normal variation, so asymmetry does appear to be a potentially useful way of detecting abnormality. In agreement with Hides et al. (1992), symmetry of shape was poorer than that of size, with large individual variation. Results at L5 were similar to those at L4. Asymmetry of muscle shape ratio was not investigated in LBP subjects and due to the large values in normal subjects, it is unlikely that this form of assessment would detect abnormality accurately. 4.3.3. Relationships between multifidus size and anthropometry The low correlations between multifidus size and general anthropometric measurements of height, body mass or BMI were contrary to those reported by Hides et al. (1992), who found significant positive correlations between L4 CSA and body mass and height. In the previous study of males, the correlation coefficient for CSA and mass was 0.78 compared to 0.14 in the present

study. It is difficult to explain these markedly different findings other than by the fact that the present subjects were considerably heavier and probably more active. Although body mass and height will influence the forces acting on the spine, and therefore to some extent affect lumbar muscle activity, multifidus is not a weight bearing muscle and a direct linear relationship between multifidus and mass or height would not be expected. Of the anthropometric measures, SPL in males at L4 had the highest correlation coefficient (0.6), which was not considered sufficient to produce a clinically useful regression equation for predicting multifidus CSA. 4.4. Practical issues in the technique of imaging multifidus Multifidus is one of the most difficult muscles to image using ultrasound. Due to the curved shape of the muscle, a convex transducer is preferable to a linear one, since more of the sound beams are perpendicular to the muscle-fascia interface and thus reflected back to the transducer. 4.4.1. Identifying landmarks and the lateral border of multifidus Care is needed to find the correct echogenic landmark. For example, an image over a facet joint will result in a smaller muscle size than over the lamina, as evident in Fig. 6. To ensure a consistent technique, images are taken at the lowest point between the facet joints, first using a longitudinal orientation to aid locating the point of true muscle depth. Accurate relocation of the external scanning site for repeated scans (as described in ‘Methods’) is also important for reliability. It is particularly difficult to image the lateral border of multifidus, which lies adjacent to longissimus. Connective tissue within normal muscle surrounds its fascicles and appears as irregular white straight or curved white lines. The fascicular structure of multifidus can sometimes be clearly identified on a scan, as the connective tissue pattern differs to that of longissimus (see Fig. 5). In some cases, although a clear border cannot be identified, it can be visualized where these different patterns meet. The shape of the muscle at L4 can vary from the round or oval shapes seen in Fig. 3, to the triangular shape in Fig. 5, which appears to occur in highly trained individuals with hypertrophied muscles. Furthermore, muscle tissues lying either side of the border move differently during contraction, assisting identification of the border. Specifically, the fascicles of multifidus move in relation to each other with a swirling action, giving a lava lamp effect (as described by Judith Pearson MCSP, personal communication, with permission). This can be demonstrated by asking the subject to lift the ipsilateral leg gently.

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Ultrasound imaging in routine physiotherapy practice: Skill of the operator can have a marked effect on the quality of images and their reliability needs to be established, following a period of practice. Adoption of ultrasound imaging of muscle by physiotherapists into routine clinical practice should involve training, including technical and safety aspects, preferably by a sonographer, to ensure the technique is used appropriately. Adherence to safety guidelines produced by the BMUS should help secure a place for muscle imaging as a recognized application in the field of medical ultrasound. 5. Conclusions Fig. 6. Biofeedback of lumbar multifidus—longitudinal view using split screen facility. The facet joints (F) can be used as landmarks for the lower borders of the muscles. During contraction (right panel), the muscle becomes thicker and the angle of the fibres becomes steeper, providing feedback. Right multifidus of female aged 46 years. (5 MHz linear probe.)

Adjustment of the angle of the transducer by tilting it in the cephalad-caudad and medial-lateral directions can help to improve the definition of muscle borders, whilst at the same time maintaining a sharp image of the echogenic lamina. Positioning of the subject: Subject positioning is important to standardize muscle length and maintain a flat lumbar spine. The standard prone position for imaging multifidus may not be suitable for people with e.g. severe LBP, neurological disorders or in post-natal women. It was found that measurements from scans taken in side lying did not differ from those taken in prone (Coldron et al., 2003), so this alternative position can be used where necessary. Visual biofeedback tool: The use of ultrasound for biofeedback has been described for facilitating lumbar mulitifidus (Hides et al., 1998) and is attracting increasing clinical interest. The muscle can be imaged transversely (observing the ‘lava lamp’ effect described above) or longitudinally over the facet joints, as illustrated in Fig. 6. Various manoeuvres are used to ilicit a contraction e.g. in forward lean standing or walk standing, the subject is asked to lift the ipsilateral leg and/or contralateral arm. Richardson et al. (1998) suggested palpating the muscle and asking the subject to swell out the muscle beneath the examiner’s fingers. As the muscle contracts, the subject can observe it on the screen as it becomes thicker and the angle of fibres become steeper (Fig. 6). The effectiveness of subject posture and the manoeuvre used vary between individuals, so it is a matter of trying different techniques to find one that suits each person. The British Medical Ultrasound Society Safety Guidelines (website: www.bmus.org) advise that exposure time is kept to the minimum necessary.

Assessment of multifidus size can be made by comparison with the 95% reference ranges reported. Separate data are needed for each gender and vertebral level but not for different age groups up to 69 years. Further data are needed for populations of different activity levels and specific sports, and people over 70 years. Changes in quality of muscle tissue with age require investigation. Shape varied considerably amongst normal subjects, suggesting that it may be inappropriate to describe a typical multifidus shape. The mean between-side difference in CSA was higher than previously reported but was still much lower than the degree of asymmetry found previously in acute LBP patients. Regression equations to predict L4 multifidus CSA from L5, and vice versa, could be used clinically, provided wasting appears to be isolated to one vertebral level. Similar relationships may exist between muscles at other levels but require investigation. Linear measurements of multifidus provide an estimate of CSA and are simple and quick to use. Ultrasound imaging is being used increasingly for research, clinical assessment and biofeedback. If ultrasound is to be adopted for use in routine physiotherapy practice, it is important that the methodology for obtaining and measuring images is standardized, to ensure the technique is robust and reliable. Acknowledgments The authors thank the subjects at the Royal Hospital for Neuro-disability who took part in the study, Dr Anthony Swan for statistical advice and data analysis, and the Neuro-disability Research Trust for financial support. References Amonoo-Kuofi HS. The density of muscle spindles in the medial, intermediate and lateral columns of human intrinsic postvertebral muscles. Journal of Anatomy 1983;136:509–19.

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Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986;1:307–10. Bogduk N. Clinical anatomy of the lumbar spine and sacrum, 3rd ed. Edinburgh: Churchill Livingstone; 1997. Bogduk N, Macintosh JE, Pearcy MJ. A universal model of the lumbar back muscles in the upright position. Spine 1992;17:897–913. Chinn S. The assessment of methods of measurement. Statistics in Medicine 1990;9:351–62. Coldron Y, Stokes M, Cook K. Lumbar multifidus muscle size does not differ whether imaging is performed in prone or side lying. Manual Therapy 2003;8:161–5. Grieve GP. Common vertebral joint problems. Edinburgh: Churchill Livingstone; 1983. Hides JA, Cooper DH, Stokes MJ. Diagnostic ultrasound imaging for measurement of the lumbar multifidus muscle in normal young adults. Physiotherapy Theory and Practice 1992;8:9–26. Hides JA, Richardson CA, Jull GA. Magnetic resonance imaging and ultrasonography of the lumbar multifidus muscle. Spine 1995; 20:54–8. Hides JA, Richardson CA, Jull GA. Multifidus muscle recovery is not automatic following resolution of acute first episode low back pain. Spine 1996;21:2763–9.

Hides JA, Richardson CA, Jull GA. Use of real-time ultrasound imaging for feedback in rehabilitation. Manual Therapy 1998;3:125–31. Hides JA, Stokes MJ, Saide M, et al. Evidence of lumbar multifidus muscle wasting ipsilateral to symptoms in patients with acute/ subacute low back pain. Spine 1994;19:165–72. Macintosh JE, Bogduk N, Valencia F, et al. The morphology of the human lumbar multifidus. Clinical Biomechanics 1986;1: 196–204. Rankin G, Stokes MJ. Reliability of assessment tools in rehabilitation: an illustration of appropriate statistical analysis. Clinical Rehabilitation 1998;12:187–99. Riddle DL, Finucane SD, Rothstein JM, et al. Intrasession and intersession reliability of hand-held dynamometer measurements taken on brain-damaged patients. Physical Therapy 1989;69: 182–94. Stokes M, Hides J, Nassiri D. Musculoskeletal ultrasound imaging: diagnostic and treatment aid in rehabilitation. Physical Therapy Reviews 1997;2:73–92. Tsubahara A, Chino N, Akaboshi K, et al. Age-related changes of water and fat content in muscles estimated by magnetic resonance (MR) imaging. Disability and Rehabilitation 1995;17: 298–304.

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Manual Therapy 10 (2005) 127–135 www.elsevier.com/locate/math

Original article

Immediate effects of thoracic manipulation in patients with neck pain: a randomized clinical trial$ Joshua A. Clelanda,b,, Maj. John D. Childsc, Meghann McRaed, Jessica A. Palmera, Thomas Stowella a

Physical Therapy Program, Franklin Pierce College, 5 Chenell Drive, Concord, NH 03301, USA b Rehabilitation Services of Concord Hospital, Concord, NH, USA c Department of Physical Therapy, Wilford Hall Medical Center, San Antonio, TX, USA d Monadnock Community Hospital, Peterborough, NH, USA Received 23 December 2003; received in revised form 14 July 2004; accepted 18 August 2004

Abstract Mechanical neck pain is a common occurrence in the general population resulting in a considerable economic burden. Often physical therapists will incorporate manual therapies directed at the cervical spine including joint mobilization and manipulation into the management of patients with cervical pain. Although the effectiveness of mobilization and manipulation of the cervical spine has been well documented, the small inherent risks associated with these techniques has led clinicians to frequently utilize manipulation directed at the thoracic spine in this patient population. It is hypothesized that thoracic spine manipulation may elicit similar therapeutic benefits as cervical spine manipulation while minimizing the magnitude of risk associated with the cervical technique. The purpose of this randomized clinical trial was to investigate the immediate effects of thoracic spine manipulation on perceived pain levels in patients presenting with neck pain. The results suggest that thoracic spine manipulation results in immediate analgesic effects in patients with mechanical neck pain. Further studies are needed to determine the effects of thoracic spine manipulation in patients with neck pain on long-term outcomes including function and disability. r 2004 Elsevier Ltd. All rights reserved. Keywords: Cervical pain; Thoracic spine manipulation; Manual therapy; Mechanical neck pain

1. Introduction Approximately 54% of individuals have experienced neck pain within the last six months (Cote et al., 1998, 2000), and the incidence appears to be rising (Nygren et al., 1995). The economic burden due to neck disorders is high, second only to low back pain in annual workers’ compensation costs in the United States (Wright et al., 1999). Patients with neck pain are frequently encountered in outpatient physical therapy practice, consisting $ Work should be attributed to the Physical Therapy Program, Franklin Pierce College, Concord, NH. Corresponding author. Franklin Pierce College, 5 Chenell Drive, Concord, NH 03301, USA. Fax: +1 603 785 5576. E-mail address: [email protected] (J.A. Cleland).

1356-689X/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2004.08.005

of approximately 25% of all patients (Jette et al., 1994). Manual therapy interventions are one treatment strategy appropriate for patients with neck pain (American Physical Therapy Association, 2001). The Guide to Physical Therapist Practice (American Physical Therapy Association, 2001) uses the term ‘‘mobilization/ manipulation’’ to refer to a ‘‘manual therapy technique comprising a continuum of skilled passive movements to the joints and/or related soft tissues that are applied at varying speeds and amplitudes, including a smallamplitude/high-velocity therapeutic movement.’’ To be more specific, the term ‘‘manipulation’’ in this paper refers specifically to techniques involving a high-velocity low-amplitude thrust, whereas mobilization refers to techniques performed as lower velocity, passive movements of a joint. Approximately 37% of therapists who

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routinely perform manual therapy interventions for patients with spinal disorders in their clinical practice perform manipulation and/or mobilization to the cervical spine in patients with neck pain (Hurley et al., 2002). The effectiveness of these interventions in patients with neck pain and cervicogenic headaches has been recently supported by an increasing number of high quality randomized clinical trials (RCT) (Bronfort et al., 2001b; Evans et al., 2002; Hoving et al., 2002; Jull et al., 2002), and systematic reviews (Bronfort et al., 2001a; Gross et al., 2002) suggesting both forms of manual therapy are effective. The benefits of manual therapy interventions directed to the cervical spine must be considered in the context of the potential risks. The risk of serious complications such as vertebrobaslilar insufficiency (VBI) has been estimated to be extremely low (approximately six in 10 million; 0.00006%) (Hurwitz et al., 1996). However, studies to date have largely failed to substantiate the ability of currently available screening procedures to identify at-risk patients prior to treatment (DiFabio, 1999). Therefore, it has been suggested that cervical manipulation interventions be abandoned altogether (Bolton et al., 1989; Cote et al., 1996; DiFabio, 1999; Haldeman et al., 1999, 2002a,b). In one survey of physical therapists in Canada, 88% of respondents strongly agreed that all available screening tests should be performed prior to cervical manipulation (Hurley et al., 2002), suggesting that therapists are indeed concerned about the risks. Therefore, some therapists may conclude the benefits achieved from manual therapy interventions directed to the cervical spine are not worth even the small risks associated with these interventions. Clinical experts have suggested that a thorough examination of the thoracic spine be included in the evaluation of patients with primary complaints of neck pain (Porterfield and DeRosa, 1995; Greenman, 1996). Due to the biomechanical relationship between the cervical and thoracic spine, perhaps disturbances in joint mobility in the thoracic spine serve as an underlying contributor to the development of neck disorders. It has also been demonstrated that mobilization/manipulation of joints remote to the patient’s pain results in an immediate hypoalgesic effect (Vicenzino et al., 1996, 1998, 2001; Paungmali et al., 2003). This is speculated to occur through the stimulation of descending inhibitory mechanisms (Vicenzino et al., 1998; Skyba et al., 2003). For these reasons it has been suggested that perhaps the incorporation of thoracic spine manipulation interventions in lieu of manipulation or mobilization interventions directed to the cervical spine may avoid even the small inherent risks associated with manual therapy interventions directed to the cervical spine, while achieving similar therapeutic benefits (Erhard and Piva, 2000).

Only scant evidence exists regarding the use of thoracic spine manipulation in patients with neck pain. Flynn and colleagues have reported preliminary data suggesting that thoracic spine manipulation results in an immediate reduction in pain and increases in cervical range of motion in individuals presenting with primary neck dysfunction (Flynn et al., 2004). However, the lack of a comparison group in this study precludes establishing that a cause-and-effect relationship exists. In addition, Parkin-Smith (Parkin-Smith and Penter, 1998) and colleagues demonstrated that thoracic manipulation in addition to cervical manipulation in patients with neck pain was no more advantageous than cervical manipulation alone. Therefore, the purpose of this study was to further investigate the immediate effects of thoracic manipulation on neck pain in a randomized clinical trial.

2. Methods Potential participants were patients between 18 and 60 years of age with a primary complaint of mechanical neck pain referred by their primary care physician to an outpatient orthopaedic physical therapy clinic. Mechanical neck pain was defined as nonspecific pain in the area of the cervicothoracic junction that is exacerbated by neck movements (Bogduk, 1984; Childs et al., 2003). The study was approved by the Institutional Review Board at Franklin Pierce College (Rindge, NH) before recruitment and data collection began. All patients provided informed consent. Patients with ‘‘red flags’’ for a serious spinal condition (e.g., infection, tumors, osteoporosis, spinal fracture, etc.) were excluded, as were individuals who were pregnant, exhibited positive neurologic signs or symptoms suggestive of nerve root involvement (eg., symptoms distal to the acromion, or diminished upper extremity reflexes, sensation, or strength), had a history of cervical or thoracic surgery, exhibited hypermobility of the thoracic spine, or those who had prior experience with spinal manipulative techniques. Prior to randomization, patients completed several self-report measures and then received a standardized history and physical examination by a licensed physical therapist. Demographic information including age, gender, past medical history, location and nature of symptoms was collected. Self-report measures included a body diagram to assess the distribution of symptoms (Mann et al., 1993). Subjects also completed the Neck Disability Index (NDI) to measure perceived disability. The NDI was collected only at baseline to assess for differences in disability between groups. The NDI is scored from 0 to 50, with higher scores corresponding to greater disability. The score is then multiplied by two and expressed as a percentage. The NDI has been

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demonstrated to be a reliable and valid assessment of disability in patients with neck pain (Vernon and Mior, 1991). A Visual Analog Scale (VAS) was used to record the patient’s level of resting pain at baseline and immediately after treatment. The VAS is a 100 mm line anchored with a ‘‘0’’ at one end representing ‘‘no pain’’ and ‘‘100’’ at the other end representing ‘‘the worst pain imaginable’’. Patients placed a mark along the line corresponding to the intensity of their symptoms, which was scored to the nearest millimeter. The VAS is a reliable and valid instrument to assess pain intensity (Price et al., 1983; Bijur et al., 2001) and was selected as the outcome measure based on its ability to detect immediate changes in pain (Bijur et al., 2001; Bird and Dickson, 2001; Gallagher et al., 2001). Following the baseline examination, the examining therapist left the treatment room and notified a second licensed physical therapist blinded to the patient’s demographic information and baseline levels of pain and disability that the subject was ready for thoracic spine segmental mobility examination and associated treatment based on group assignment. Segmental mobility testing was performed in the positions of thoracic spine flexion and extension according to the procedures described by Bookhout (1994). The specific level(s) and position of restriction was recorded. The intrarater reliability of accurately identifying the specific level of segmental mobility restriction in the thoracic spine is poor (Kappa=.33) (Christensen et al., 2002). Following the segmental mobility examination, patients were randomly assigned to receive either thoracic spine manipulation or placebo manipulation. A computer-generated randomized table of numbers created prior to the beginning of the study was utilized to determine group assignment. The patient’s group assignment was sealed in a sequentially numbered opaque envelope and was opened after the treating therapist

129

completed the segmental mobility examination. Treatment was then administered according to the patient’s group assignment. The treating therapist was therefore unaware of the patient’s group assignment during the segmental mobility examination. 2.1. Manipulation group Patients randomized to the manipulation group received thoracic manipulation interventions directed to the previously identified segmental mobility restrictions. To perform the manipulation, the stabilizing hand was placed at the level immediately caudal to the restricted segment using a ‘‘pistol grip’’ (Fig. 1). Once the premanipulative position was achieved the patient was instructed to take a deep inhalation and exhale. During the exhalation the treating clinician performed a high velocity, small amplitude thrust in a direction to facilitate relative closing or opening of the respective facet joint as indicated by the segmental examination (Fig. 2) (Flynn, 1994). If an audible cavitation was heard during the first manipulation attempt, the treating clinician proceeded to the next segment. If no audible cavitation was heard, the patient was repositioned, and the manipulation intervention was repeated at the same segment. If no audible cavitation was noted after two attempts, the physical therapist manipulated the next segmental restriction. This procedure was repeated for each segmental mobility restriction identified, progressing sequentially from cephalad to caudad. The level at which treatment was directed and whether an audible cavitation was achieved was recorded. There is little evidence to suggest that the thoracic spine manipulation interventions used in this study are specific for an individual level (Isaacs and Bookhout, 2002). Even presuming they are, it is possible that the lack of reliability to accurately identify individual

Fig. 1. Hand positioning utilized during manipulation techniques (actual technique performed with skin to skin contact).

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Fig. 2. Manipulation technique for a flexion restriction. High velocity, small amplitude thrust performed in the direction of the arrow.

segmental motion restrictions (Christensen et al., 2002), means that the segment presumed to be restricted may not be the same segment at which the thoracic spine manipulation intervention was directed. However, this procedure is consistent with standard of care practice during thoracic spine manipulation in patients with neck pain at our facility, and we are unaware of another decision-making scheme preferable to this one.

2.2. Placebo manipulation group Patients randomized to receive placebo thoracic spine manipulation were placed in the identical set up position as patients in the manipulation group with the exception of hand positioning. An ‘‘open hand’’ was placed over the inferior vertebrae of the pre-determined segmental restriction. Once the ‘‘premanipulative position’’ was achieved, the patient was instructed to take a deep inhalation and then exhale. No high-velocity thrust maneuver was performed during the exhalation. The level at which the placebo or manipulation intervention was directed and whether an audible cavitation was achieved were both recorded. Given that patients with previous exposure to spinal manipulation were excluded from the study, it is unlikely that patients were aware that a high-velocity thrust maneuver is usually performed during this manipulation intervention. The therapist who performed the baseline examination then re-entered the room, remaining blinded to the patient’s group assignment. The patient was asked to report their perceived level of pain intensity on the VAS after treatment. This assessment was always performed within 5 min after completing treatment. All subjects were instructed to contact the principal investigator if they experienced any side effect (soreness lasting greater than 3 h).

2.3. Data analysis Baseline demographic and self-report measures of pain and disability were compared between groups using independent t-tests or Mann–Whitney U tests for continuous data, and w2 tests of independence for categorical data (Table 1). A two-way repeated measures analysis of variance (ANOVA) was used to assess the change in pain intensity immediately after treatment. Intervention (thoracic spine manipulation or placebo manipulation) served as the between-subjects independent variable and Time (baseline and immediately after treatment) served as the repeated measures factor. The hypothesis of interest was the two-way InterventionTime interaction based on an a priori determined alpha-level equal to .05. We hypothesized that patients who received thoracic spine manipulation would experience greater immediate improvements in pain than patients who received placebo manipulation. All data analysis was performed using the SPSS Version 10.1 statistical software package (SPSS Inc, Chicago, IL).

3. Results Sixty-eight patients were screened for eligibility during a six-month period from January 2003 to June 2003. Sixteen patients (24%) did not satisfy the inclusion and exclusion criteria for the study. Sixteen eligible patients (31%) elected not to participate because of preferring not to receive manipulation interventions (n=11) or specifically requesting manipulation (n=5). The remaining 36 patients, mean age equal to 36 (SD=9.8) (27 female), were randomized to receive thoracic spine manipulation (n=19) or placebo manipulation (n=17) (Fig. 3).

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Table 1 The results of statistical analysis between manipulation and placebo manipulation groups for demographics and pretreatment visual analog score data

Age mean (SD); Gender mean (SD); Symptom Duration (in weeks) mean (SD); VAS pretreatment mean (SD); VAS post treatment means (SD); VAS change score mean (SD); Number of manipulations or placebo manipulations mean (SD); NDI mean (SD)

Manipulation group (n=19)

Placebo manipulation group (n=17)

P

36 (8.5) 14 females 12.2 (3.5) 41.6 (17.8) 26.1 (17.2) 15.5 (7.7) 3.7 (.83) 28.4 (11.9)

35 (11.3) 13 females 13.2 (4.2) 47.7 (18.4) 43.5 (19.5) 4.2 (4.6) 3.0 (.89) 33.6 (14.2)

.742 .849 .460 .323 o.01 o.001 .291 .237

VAS=Visual analog scale. NDI=Neck disability index.

68 patients referred to physical therapy with a diagnosis of cervical pain

52 eligible

16 ineligible: 7- fell outside age range for inclusion 5- presented with radicular symptoms 2- pregnant females 1- prior history of cervical surgery 1- history of thoracic fracture

16 refused to participate: 11- preferred not to receive manipulation 5- specifically requested manipulation 36 randomized

19 received thoracic manipulation

17 received placebo manipulation

Fig. 3. Flow chart depicting subject selection and randomization.

No differences in key demographic variables or baseline levels of pain and disability were detected between the groups at baseline (P4.05) (Table 1). The repeated measures ANOVA demonstrated a significant InterventionTime interaction (Po.001) (Fig. 4), suggesting that patients receiving thoracic spine manipulation experienced immediate improvements in pain

compared to patients in the placebo group. The change in pain in the group receiving thoracic spine manipulation was 15.5 mm (SD 7.7) mm (95% CI: 11.8, 19.2), compared to a change in the group receiving placebo manipulation of 4.2 mm (SD 4.6) (95% CI: 1.9, 6.6). The number of thoracic spine manipulations and placebo manipulations in each group was 3.7 and 3.0,

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Intercept Graph for VAS Scores of *Intervention* Time (P< 0.001) 50 47.7

VAS Score

45 40

43.7

41.6

35 30 25

Manipulation Placebo

25.6

20 Pretest

Posttest

Fig. 4. Intercept graph for visual analog scores of *Intervention* Time (Po.001).

respectively (P=.29). No subjects in either group contacted the principal investigator after the completion of the study to report any side effects. Considering this we expect that no one experienced any sensation more than mild soreness following treatment or placebo.

4. Discussion The results of this study suggest that thoracic spine manipulation in patients with a primary complaint of neck pain results in immediate improvements in their neck pain. Patients receiving thoracic spine manipulation demonstrated a mean change of 15.5 mm (95% CI: 11.8–19.2) on the VAS, compared to only a 4.2 mm (95% CI: 1.9–6.6) change among patients in the placebo group. Even if one presumes the lower bound of the 95% CI of 11.8 to be the point estimate for patients receiving thoracic spine manipulation, this magnitude of change still represents a clinically meaningful level of improvement (Kelly, 1998; Bird and Dickson, 2001; Kelly, 2001; Gallagher et al., 2001). In contrast, even if one conservatively presumes the upper bound of the 95% CI of 6.6 to be the point estimate for patients in the placebo group, this magnitude of change falls below the necessary level of change to substantiate that a clinically meaningful change has occurred (Kelly, 1998; Bird and Dickson, 2001; Kelly, 2001; Gallagher et al., 2001). Despite evidence for its effectiveness, considerable attention has been given to the risk of serious complications such as vertebrobasilar insufficiency (VBI) from manual therapy interventions directed to the cervical spine (Hurwitz et al., 1996; DiFabio, 1999; Haldeman et al., 1999, 2002a,b). However, recent evidence suggests that cervical spine manipulation is beneficial for some patients (Cassidy et al., 1992; Hurwitz, 1996; Nilsson et al., 1997). Moreover, using techniques that place the patient’s neck in a more

neutral position (i.e. avoiding the terminal range of extension and rotation) appears to be a prudent strategy to minimize these risks and may be a more important consideration than the amount of force used (Mann and Refshauge, 2001; Symons et al., 2002). Therefore, we are not suggesting that cervical spine manipulation be avoided. However, the results of this study suggest that thoracic spine manipulation may be a reasonable alternative, or perhaps supplement to manual therapy interventions directed to the cervical spine. ParkinSmith and Penter (1998) demonstrated that manipulating both the cervical and upper thoracic spine did not result in any significant benefits over patients receiving cervical manipulation, for neck pain. However, it was reported that some of the patients also received soft tissue massage yet the number of individuals or their group assignment was not reported. Therefore it is unknown if this added variable could have affected patient outcomes. Despite the limited evidence for thoracic spine manipulation, many clinicians have intuitively adopted this same practice presumably because of less concern about risks with thoracic spine manipulation (Adams and Sim, 1998). A recent survey among clinicians that practice manual therapy reported that the thoracic spine is the region of the spine most often manipulated, despite the fact that more patients complain of neck pain (Adams and Sim 1998). The precise mechanism by which thoracic spine manipulation improves neck pain remains elusive. It has been suggested that reductions in neck pain from thoracic spine manipulation interventions may be attributable to a restoration of more normal biomechanics to this region, potentially lowering mechanical stresses and improving the distribution of joint forces in the cervical spine. The theory that a biomechanical link between the thoracic and cervical spine may lead to abnormal distribution of forces in the cervical spine has only recently been investigated. Norlander et al. (1996, 1997), Norlander and Nordgren (1998) investigated whether mobility in the cervico-thoracic motion segment is associated with musculoskeletal neck-shoulder pain. They reported a significant relationship between decreased mobility in the thoracic spine and the presence of subjective complaints associated with neck pain (Norlander et al. 1996, 1997; Norlander and Nordgren, 1998). This hypothesis would have been further supported if we had collected measures related to musculoskeletal impairments such as cervical range of motion. Several recent studies (Vicenzino et al., 1996, 2001; McLean et al., 2002; Coppieters et al., 2003) have demonstrated that manual therapy interventions directed at the spine can result in improvements in pain in regions distant to the area in which the treatment is directed. In addition, recent studies (Chiradejnant et al., 2003; Haas et al., 2003) have demonstrated that

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mobilization/manipulation techniques directed at impaired motion segments were no more beneficial than the treatment of randomly selected segments. It has been speculated that the immediate hypoalgesia following manual techniques directed at the spine may be related to stimulation of descending inhibitory mechanisms. (Vicenzino et al., 1998; Skyba et al., 2003). We acknowledge several limitations. First, we limited this study to a short-term follow-up based on this study serving as a preliminary step in the investigation of the effects of thoracic spine manipulation in patients with neck pain. However, the fact that statistically significant and clinically meaningful change occurred over such a short time frame among patients who received thoracic spine manipulation bolsters the argument that these changes are likely relevant for patients with neck pain, providing impetus for future research in this area. Additionally, examining changes in cervical range of motion could have provided further insight as to the biomechanical implications associated with thoracic spine manipulation in patients with neck pain. Although we did not measure cervical spine ROM in this study, preliminary evidence (Flynn et al., 2004) suggests that thoracic spine manipulation is associated with immediate improvements in cervical spine ROM, providing a theoretical construct by which thoracic spine manipulation may act to improve pain in patients with a primary neck complaint. Future research in this area should examine the longterm effects of thoracic spine manipulation in patients with neck pain on outcomes of care, patient satisfaction, and costs. Head-to-head clinical trials are also needed to determine if thoracic spine manipulation is most beneficial in isolation, or if it should in some combination as a supplement to manual therapy interventions directed to the cervical spine. Given the recent development and validation of a clinical prediction rule to identify patients with low back pain likely to experience a successful outcome from spinal manipulation (Flynn et al., 2002), perhaps the development of a clinical prediction rule would be advantageous to identify whether a subgroup of patients with a primary complaint of neck pain exists that may benefit from a manual therapy treatment approach directed primarily to the thoracic spine.

5. Conclusion Thoracic spine manipulation results in immediate improvements in perceived levels of cervical pain in patients with mechanical neck pain. Given the concern regarding the risks of cervical spine manipulation, perhaps thoracic spine manipulation is a reasonable alternative, or supplement to, cervical manipulation and mobilization to maximize the patient’s outcome at a

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reasonably low level of risk. This study was limited to an immediate follow-up and the patient’s perceived levels of pain, thus further research is needed to examine the longer-term effects of thoracic spine manipulation on patient-centered outcomes and determine if relevant subgroups of patients with neck pain exist who may particularly benefit from thoracic spine manipulation interventions.

Disclaimer The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the U.S. Air Force or Department of Defense.

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Manual Therapy 10 (2005) 136–143 www.elsevier.com/locate/math

Original article

Effect of straight leg raise examination and treatment on vibration thresholds in the lower limb: a pilot study in asymptomatic subjects Colette Ridehalgha,, Jane Greeningb, Nicola J. Pettya a

School of Health Professions, Clinical Research Centre for Health Professions, University of Brighton, ALDRO building, 49 Darley Road, Eastbourne BN20 7UR, UK b 52 Woodside, Sevenoaks, Kent, TN13 3HF, UK Received 4 August 2003; received in revised form 13 July 2004; accepted 18 August 2004

Abstract Individuals who participate in repetitive functional activities may have alteration in large diameter neural activity. It has been proposed that neurodynamic examination and treatment may affect large diameter afferent activity, and that neurological integrity tests should be carried out prior to neurodynamic testing. Vibration threshold testing (VTT) has been shown to be a valid measure of large diameter afferent conduction. The aim of this study was to assess whether examination and treatment of straight leg raise with plantar flexion and inversion (SLR) has an effect on the conduction of large diameter afferents supplying the lower leg in normal subjects and in a group of runners. Twenty sedentary asymptomatic subjects and 10 asymptomatic runners underwent VTT at the second and fourth metatarsals (representing the distribution of the superficial peroneal nerve) before and after examination of the SLR and after a mimicked treatment with SLR (VTT carried out immediately and 10 min after treatment). A repeated measures ANOVA revealed no significant baseline differences in VT between runners and non-runners (P ¼ 0:171), or between any of the four test conditions in either group (P ¼ 0:5). Although not significant there was a trend for runners to have raised mean VT compared to non-runners, and for SLR treatment to cause an elevation in VT in both groups. These results suggest that examination and treatment of SLR may not be detrimental to function of the large diameter afferents in asymptomatic subjects. r 2004 Elsevier Ltd. All rights reserved.

1. Introduction Injury to the peripheral nervous system leading to increased nerve mechanosensitivity and change in neural dynamics is thought to contribute to some musculoskeletal pain syndromes (Katavich, 1999), and the use of neurodynamic tests have been advocated to assess and treat such injuries (Elvey, 1986; Butler, 1991, 2000; Koury and Scarpelli, 1994; Fidel et al., 1996; Shacklock, 1996; Katavich, 1997; Yeung et al., 1997). Treatment with neurodynamic mobilization has been suggested as a means of restoring normal mechanical and physiological function to the nervous system (Butler, 1991, 2000; Shacklock, 1995; Katavich, 1997). It has been suggested Corresponding author. Tel.: +44 1273 643686; fax: +44 1273 643652. E-mail address: [email protected] (C. Ridehalgh).

1356-689X/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2004.08.008

in animal studies that lengthening nervous tissue to greater than 6–15% of its total length may be detrimental to nerve function (Lundborg and Rydevik, 1973; Lundborg, 1975; Ogato and Naito, 1986; Wall et al., 1992; Humphreys et al., 1998). A number of studies have attempted to measure movement of the peripheral nerves in cadavers during limb motion (Wright et al., 1996; Zoech et al., 1991), and make estimates about the percentage change in length occurring. However, the actual percentage increase in length of human nervous tissue in vivo during neurodynamic tests is difficult to assess due to the complexity of the movements of the nervous tissue, and surrounding tissue that occur during movements of the limbs (Butler, 1991, 2000). Length changes occurring at the nerve bed during neurodynamic testing, and the pressure changes that occur in and around the nerve may also be detrimental to nerve function (Rydevik and Lundborg,

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1977; Ogato and Naito, 1986; Powell and Myers, 1986; Rempel et al., 1999). Pressures recorded around the carpal tunnel during sustained wrist flexion to extension have been as high as 30 mm Hg (Gelberman et al., 1981) in asymptomatic subjects. Applying such pressures to peripheral nerves has resulted in inflammatory changes around the nerve and a reduction in nerve conduction (Rydevik and Lundborg, 1977; Gelberman et al., 1983). Two studies have looked for a change in nerve function during neurodynamic assessment as assessed by altered nerve conduction. Humphreys et al. (1998) found that in a small group of 10 asymptomatic subjects, positioning the leg in the straight leg raise (SLR) position adversely affected nerve conduction as demonstrated by an increase in F wave latency. This suggested a dysfunction in the conduction of the proximal nerve segments (Robinson and Snyder-Mackler, 1995). However it must be noted that such small numbers of subjects used in this study make extrapolation of these findings to the general population uncertain. Spencer (1995) sustained the upper limb tension test 2, biasing the median nerve, in 15 male subjects. After 20 min deterioration in nerve conduction was found, but was not statistically significantly different to baseline figures. Due to the lack of evidence regarding the effects of neurodynamic testing on nerve conduction, it has been suggested that neurological integrity should be tested prior to neurodynamic testing or treatment (Butler, 1991). 1.1. Measuring peripheral nerve function Electro-diagnostic tests are often negative when measuring minor peripheral nerve pathology (Borg and Lindblom, 1986; Greening, 1994; Greening and Lynn, 1998a, b; Styf, 1988). It has been proposed that vibration threshold testing (VTT) can detect early signs of minor nerve damage (Goldberg and Lindblom, 1979; Lundborg et al., 1992; Greening and Lynn, 1998a, b; Martina et al., 1998; Greening et al., 2002), since the large diameter afferent nerve fibres (Ab), which mediate the sensation of vibration, are more vulnerable to ischaemia than other nerve fibres (Phillips et al., 1987; Martina et al., 1998). VTT has been shown to be a reliable and valid method of measuring nerve function (Goldberg and Lindblom, 1979; Halonen, 1986; Phillips et al., 1987; Hilz et al., 1998; Martina et al., 1998; Valk et al., 2000). VTT has been used as a method of detecting early minor peripheral nerve damage in a number of patient groups (Borg and Lindblom, 1986; Phillips et al., 1987; Lundborg et al., 1992; Greening and Lynn, 1998a; Martina et al., 1998; Hammond, 2000; Valk et al., 2000; Greening et al., 2003). Using VTT as a measure of nerve dysfunction has recently identified that those individuals who participate in repetitive activity may be vulnerable to nerve injury

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(Greening and Lynn, 1998a; Hammond, 2000; Greening et al., 2003). Runners are thought to be at risk of injury to the common peroneal portion of the sciatic nerve, because of the forceful repetitive movements that occur in the lower limb during running (Mayfield and True, 1973; Garfin et al., 1977; Leach and Purnell, 1989; Fabre et al., 1998; McCrory et al., 2002), and due to the high incidence of ankle sprains reported in this group of individuals (Kopell and Thompson, 1963; Garrick, 1977). A number of studies have demonstrated that common peroneal nerve damage may occur after plantarflexion/inversion (PF/INV) sprains (Nitz et al., 1985; Kleinrensink et al., 1994; Pahor and Toppenberg, 1996). Together, these factors may predispose the common peroneal nerve to minor nerve damage in this group of individuals. Subjects who have minor nerve injury may demonstrate a susceptibility to positions or activities, which compromise the blood supply to the nerve (Borg and Lindblom, 1986; Greening and Lynn, 1998a; Hammond, 2000), causing a further deterioration in vibration thresholds. Straight leg raise with plantar flexion and inversion (SLR PF/INV) sensitizes the common peroneal nerve portion of the sciatic nerve (Slater, 1989; Butler, 1991, 2000). It may be therefore that runners are more susceptible to a change in nerve function resulting from a SLR PF/INV procedure than non-runners. This study was undertaken to investigate whether assessment and treatment of the common peroneal nerve with SLR PF/INV, had an effect on vibration thresholds in the lower leg supplied by the superficial peroneal nerve, in normal healthy subjects, and to compare these data with those obtained from a small group of runners. It was hypothesized that an increase in vibration threshold would occur after SLR PF/INV and that this effect would be greater in the runners. It was also hypothesized that runners would have a higher baseline vibration threshold than non-runners.

2. Methods 2.1. Subjects Twenty asymptomatic subjects (10 female and 10 male) with a mean age 30.2 years (SD 3.6), with no previous history of low back or lower limb symptoms were recruited for this study. They did not run greater than 5 miles per week and were classified as nonrunners. Ten asymptomatic subjects (7 male and 3 female) with a mean age of 31.8 years (SD 6.4) who ran greater than twenty miles per week were recruited from various sports clubs (running, professional football, and professional county cricket). These subjects were classified as runners. Past history of low back or lower limb

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symptoms were permitted in this group, but subjects with current symptoms were excluded. All subjects were excluded if they had any systematic disorders or neurological conditions, or if they had positive neurological integrity tests or a restriction in their range of ankle motion. Ethical approval was obtained from the University College London Ethics Committee and all subjects gave written informed consent.

Subject seated baseline VT measurements of 2nd and 4th metatarsals left and right feet taken

↓ Subject in supine-one leg positioned in SLR PF/INV

↓

2.2. Equipment Vibration threshold was tested with a vibrametre (Somedic AB, Stockholme, Sweden). The tissue displacement range was 0.1–400 mm and frequency was set at 100 Hz (  2 Alternating current). The pressure applied by the hand held stimulator was standardized to approximately 650 g, by means of a pressure display of 0–100 g. A digital display revealed the tissue displacement produced by the vibrating probe. The validity and reliability of the vibrametre has previously been demonstrated elsewhere (Goldberg and Lindblom, 1979; Halonen, 1986; Hilz et al., 1998; Martina et al., 1998). 2.3. Intra-rater reliability The intra- rater reliability of the researcher using the vibrametre was tested. Five successive vibration threshold readings were taken from the second and fourth metatarsal heads of both feet in one subject over two days. The coefficient of variance revealed low percentages for each of the readings (ranging from 4.8% to 12.3%) suggesting that variability between readings was also low (Munro, 1997), and intra-rater reliability was satisfactory.

Subject seated - VT retested on the same leg

↓ Subject in supine-leg positioned in SLRPF/INV ankle mobilised into resistance (PF/INV) 3 X 1 minute

↓ Subject seated- repeat VT measurements on the same leg

↓ Subject seated after 10minutes repeat VT measurements on the same leg.

↓ Procedure repeated on the opposite leg

Fig. 1. Flow chart of methodological procedure.

2.4. Procedure

Table 1 Previous injuries in the group of runners

The flow chart of the procedure is shown in Fig. 1. Runners were asked to report on any previous symptoms in the lower limb (see Table 1). To familiarize the subject to the vibrametre a practice test was performed. The stimulator was applied to the dorsum of the foot, above the base of the second metatarsal bone. The technique used was identical to the experimental procedure and is described below. The stimulator portion of the vibrametre was placed on the dorsum of the foot over the second or fourth metatarsal heads with the subject in a supported seated position. Subjects were asked to close their eyes and concentrate on the stimulus. Vision is the modality thought to have an individual’s primary attention (Posner et al., 1976) therefore removal of vision when performing a task may focus the attention to other nonvisual activities. Baseline readings were then taken from

Injuries

Numbers of subjects

Ankle sprains Stress fracture tibia Muscle Strain Medial collateral ligament sprain Plantar fasciitis Sacroiliac joint pain Lateral foot pain Meniscal tear

3 1 1 1 1 1 1 1

the left and right second and fourth metatarsal head sites, the order of which was randomized. Both appearance and disappearance of the sensation of vibration were measured. Appearance of vibration was measured by turning up the vibration stimuli until the subject was just able to perceive vibration.

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Disappearance was measured by increasing the stimuli to above that of the appearance value, and then slowly reducing the stimuli to where the subject no longer felt the stimulus. Three readings of appearance and disappearance were taken from the second and fourth metatarsal heads of the left and right feet. With the subject lying supine, the researcher passively moved either ankle into full PF/INV, followed by hip medial rotation, adduction and flexion in that sequence. This constituted the SLR PF/INV test position. The choice of leg was randomly allocated by asking the subject to choose between the researcher’s left or right hand, and this limb was tested first. All movements were taken to end of range where the examiner felt maximal resistance to movement, or until any pain or paraesthesia were felt by the subject. If this occurred, the movement component reproducing these symptoms was decreased marginally until symptoms subsided and then the additional component was added. The leg was then repositioned back onto the plinth (and therefore the SLR position was not sustained), the subject sat upright, and vibration thresholds were retested using the method previously described on that same leg. The researcher then repositioned the subject’s leg in the SLR PF/INV position whilst lying supine as described above. In this position, the ankle was then oscillated for 1 min into resistance (R2) in PF/INV. The leg was returned to its resting position on the plinth for a 1-min rest period and the procedure was repeated. In total 3 min of oscillatory ankle PF/INV movements were carried out with a 1-min rest between. These rest periods were included to reflect a period of reassessment that may occur in clinical practice. After the three sets of mobilization, the subject was re-seated and vibration thresholds were re-measured immediately and again after a rest period of 10 min. After this time, the procedure was repeated on the opposite leg.

2.5. Data analysis The mean values for appearance and disappearance were calculated from the three vibration threshold measurements at each test site (second and fourth metatarsal heads of the left and right feet). Vibration perception was calculated by taking the average of the two resultant figures (i.e. mean of the three appearance measures and mean of the three disappearance measures). This technique is known as the method of limits (Goldberg and Lindblom, 1979; Greening and Lynn, 1998a) and was chosen to improve the reliability of VTT (Goldberg and Lindblom, 1979; Halonen, 1986).

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The data were not normally distributed, and were therefore transformed by taking logarithms prior to statistical analysis (Munro, 1997). The following analyses were performed: differences between left and right feet (paired sample T test); differences between the second and fourth metatarsal heads, differences between each of the four measurements (i.e. baseline, after SLR PF/INV, after mobilization with SLR PF/INV, and after a 10 min rest), and differences in vibration threshold readings between runners and non-runners (repeated measures analysis of variance). Critical P value was set at 0.05.

3. Results 3.1. Left versus right There was no significant difference in vibration threshold of baseline measures between left or right in either the group of non-runners (P40:28) or runners (P40:54). The vibration thresholds for the left and the right feet were therefore averaged and these values were used in all other statistical analysis. 3.2. Second metatarsal readings versus fourth metatarsal readings There was no significant difference in vibration threshold readings between the second metatarsal mean=1.07 mm (SD=0.65; range=0.3–2.84 mm) and fourth metatarsal mean=1.34 mm (SD=0.77; range=0.32–3.87 mm) test sites for runners and non-runners (P40:077). 3.3. Runners versus non-runners There was no significant difference in vibration thresholds between runners and non-runners (P40:171). Fig. 2 demonstrates that there was a trend for runners (mean=1.24 mm; SD=0.75; range 0.6–2.6 mm) to have higher vibration thresholds than the non-runners (mean=1.17 mm; SD=0.8; range 0.3–3.3 mm). 3.4. Effects of SLR PF/INV on vibration thresholds Statistical analysis revealed no significant differences in either group between the four vibration threshold readings (P40:5). Table 2 shows mean, standard deviations and confidence intervals for both groups. Fig. 2 demonstrates that for both groups, the vibration thresholds rise immediately after treatment, and that this rise is greater in runners. In most cases the vibration thresholds fall again after 10 min.

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4. Discussion The results of this study did not provide evidence to support the hypothesis that examination and treatment using SLR PF/INV elevated vibration thresholds in the region of the superficial peroneal nerve in asymptomatic subjects. The mean values of both groups demonstrated a small non-significant rise in vibration threshold after testing and treatment with SLR PF/INV, which reduced after the 10-min rest, this being slightly more apparent in the runners. A rise in vibration threshold would indicate deterioration in function of the large diameter afferent nerve fibres (Ab), suggesting a change in neuronal function possibly due to reduction in neuronal circulation or fascicular damage (Goldberg and Lindblom, 1979; Greening and Lynn, 1998a; Hilz et al., 1998; Lundborg et al., 1992; Phillips et al., 1987;Valk et al., 2000). Two other studies have looked for changes in

Non-runners 2nd metatarsal

Non-runners 4th metatarsal

Runners 2nd metatarsal

Runners 4th metatarsal

Vibration threshold

2

1.5

1

0.5

Baseline

Post test

Post treatment 10 mins after treatment

Fig. 2. Plot of mean vibration thresholds (mm) in runners and nonrunners taken at the 2nd and 4th Metatarsal heads.

nerve function during neurodynamic testing (Spencer, 1995; Humphreys et al., 1998). Both of these studies measured nerve conduction by electrodiagnostic tests, which may be less sensitive to early changes in nerve function than VT (Borg and Lindblom, 1986; Greening, 1994; Greening and Lynn, 1998a, b; Styf, 1998). Spencer (1995) applied a sustained stretch to the median nerve in 15 asymptomatic male subjects for a period of 20 min. Although changes in latency and conduction velocity occurred, they were not significant. In contrast with the findings of Spencer (1995) and the present study, Humphreys et al. (1998) demonstrated a statistically significant increase in F wave latency of the tibial nerve with the leg positioned in SLR than with the leg in a neutral position, indicating dysfunction in the conduction of the S1 nerve root. The differences in findings between the studies could be explained by methodological differences. Humphreys et al. (1998) measured F wave latency with the leg in the SLR position, whereas in the present study measurements were taken after the leg had been positioned in SLR (i.e. in sitting) This could suggest that any changes in nerve function are transient, this is supported in part by the present study, in that any rises in VT after SLR PF/INV reduced after 10 min. It may have been more appropriate to test the VT in the SLR position as did Humphreys et al. (1998), rather than sitting, as a change in stresses imposed on the superficial peroneal nerve may have occurred with the knee flexed. The VT readings of runners were higher than those of non-runners but this was not significant (P40:171). It was hypothesized that the VT of runners may be higher than that of non-runners as it has been suggested that runners may be more susceptible to common peroneal nerve injury due to the repetitive nature of the sport, and high incidence of ankle injuries (Black et al., 1990; Kleinrensink et al., 1994; Leach and Purnell, 1989; McCrory et al., 2002; Nitz et al., 1985; Pahor and Toppenberg, 1996; Styf, 1988). To the authors

Table 2 Mean values and confidence intervals of vibration thresholds in non-runners and runners before and after SLR PF/INV Non-runners

Runners

Mean (SD)

CI (lower band and upper band)

Mean (SD)

CI (lower band and upper band)

Second MT Baseline Post test Post treat 10 min after

0.97 (0.59) 1.0 (0.68) 1.07 (0.89) 1.04 (0.92)

0.69 0.68 0.65 0.61

1.25 1.32 1.49 1.47

1.17 1.54 1.64 1.53

(0.7) (1.2) (1.1) (1.1)

0.67 0.68 0.85 0.74

1.67 2.4 2.43 2.32

Fourth MT Baseline Post test Post treat 10 min after

1.17 1.11 1.27 1.28

0.75 0.71 0.66 0.67

1.49 1.51 1.88 1.89

1.51 1.44 1.77 1.68

(0.6) (0.7) (1.1) (1.1)

1.08 0.94 0.98 0.89

1.94 1.94 2.56 2.47

(0.9) (0.86) (1.3) (1.3)

MT: VT Measurement from metatarsal bone.

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knowledge no comparable study has looked at this aspect of nerve conduction in asymptomatic runners. Work done on a group of subjects who also participate in repetitive activity; keyboard workers, has demonstrated an elevation in VT compared to non-keyboard users (Greening and Lynn, 1998a; Hammond, 2000; Greening et al., 2003). If a statistically significant rise in vibration thresholds in the group of runners had been found the large diameter afferents in this group may have been pre-compromised, and the addition of SLR may have caused any endoneurial vessel and fascicular damage to reach a critical level. Other studies have found that imposing activities or positions in subjects with neuropathy, may further compromise the nerve resulting in further deterioration in nerve function (Borg and Lindblom, 1986; Valls-Sole et al., 1995; Greening and Lynn, 1998a). Keyboard users diagnosed with repetitive strain injury showed significant increases in VT of the median nerve after 5 min typing (Greening and Lynn, 1998a). During wrist flexion of up to 16 min, patients with carpal tunnel syndrome showed a marked rise in VT in the median nerve (Borg and Lindblom, 1986). These studies contrast with the present study for a number of reasons. Firstly, many of the activities described in these studies were in positions in which the nerve bed was compressed rather than elongated, and often replicated those positions which may have been the cause of the original neuropathy. In the present study, SLRPF/INV was performed, which did not replicate the normal running action. Secondly, the positions or activities were carried out for longer periods of time than the SLR procedure. A maximum time of 1 min was held during the mobilization procedure and this may not have been long enough to show change. It was not considered appropriate to sustain this position for longer than 1 min as it was felt that this would not reflect current clinical practice. Thirdly, and possibly most significantly, the subjects used in the described studies were complaining of symptoms of nerve damage, such as paraesthesia, anaesthesia and muscle weakness. The amount of fascicular damage may be greater than in subjects without such symptoms, and therefore be more susceptible to changes in neural blood flow (Greening and Lynn, 1998a). If the runners in this study were suffering from minor nerve pathology, they may have been in early stages of fascicular damage and therefore have been less susceptible to the effects of nerve elongation (SLR) than subjects complaining of symptoms of nerve damage. The small numbers of subjects used in the present study along with the high standard deviations found, may explain why the increases in VT in the group of runners were not significant. It is also proposed that the group undertake a period of running prior to VT testing which may compromise the nerve prior to testing.

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The authors acknowledge that this pilot study has a number of limitations, which will need to be addressed in any future studies. Firstly the investigator was not blinded to the group allocation, which could have unintentionally lead to bias when measuring the vibration thresholds in each group. Secondly no placebo assessment or treatment groups were utilized. This would ensure that any changes in vibration threshold (if present) are most likely to be due to the SLR test/ treatment itself, and not simply by movement of associated joints. This study found that examination and treatment with SLR had no significant effect on large diameter afferent activity. This suggests that neurodynamic assessment and treatment may not be detrimental to the function of the large diameter afferents and therefore neurological integrity testing prior to assessment or treatment may not be necessary in asymptomatic subjects. However, subjects in this study were asymptomatic and therefore the function of the large sensory fibres in the peroneal nerve may not have reached a critical level, where they became susceptible to neurodynamic testing and treatment. The small numbers of subjects used in the trial makes the results of this study not conclusive.

5. Conclusion These results suggest that neurodynamic examination and treatment with SLR/PF INV may not be detrimental to function of the large diameter afferents in asymptomatic subjects. Since these fibres are postulated to be the first to show signs of dysfunction (Lundborg et al., 1992; Martina et al., 1998; Phillips et al., 1987), this implies that nerve conduction may not be affected after SLR PF/ INV in asymptomatic subjects.

Acknowledgements The authors would like to thank U.C.L. for the use of the vibrametre (AB Somedic) and a room to collect the data from subjects, and Liz Cheek at the University of Brighton for statistical advice for this project. References Black KP, Schultz TK, Cheung NL. Compartment syndrome in athletes. Clinics in Sports Medicine 1990;9(2):471–87. Borg K, Lindblom U. Increase of vibration threshold during wrist flexion in patients with carpal tunnel syndrome. Pain 1986;26: 211–9. Butler D. Mobilisation of the nervous system. Melbourne: Churchill Livingstone; 1991. Butler D. The sensitive nervous system. Adelaide: Noigroup; 2000.

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Manual Therapy 10 (2005) 144–153 www.elsevier.com/locate/math

Original article

Abdominal muscle recruitment during a range of voluntary exercises Donna M. Urquharta,b,, Paul W. Hodgesc,d, Trevor J. Allenb, Ian H. Storyb a

Department of Epidemiology and Preventive Medicine, Monash University, Central and Eastern Clinical School, Alfred Hospital, Commercial Rd, Melbourne, Victoria 3004, Australia b School of Physiotherapy, The University of Melbourne, Victoria, Australia c Prince of Wales Medical Research Institute, New South Wales, Australia d Department of Physiotherapy, The University of Queensland, Queensland, Australia Received 5 March 2003; received in revised form 11 August 2004; accepted 27 August 2004

Abstract Various exercises are used to retrain the abdominal muscles in the management of low back pain and other musculoskeletal disorders. However, few studies have directly investigated the activity of all the abdominal muscles or the recruitment of regions of the abdominal muscles during these manoeuvres. This study examined the activity of different regions of transversus abdominis (TrA), obliquus internus (OI) and externus abdominis (OE), and rectus abdominis (RA), and movement of the lumbar spine, pelvis and abdomen during inward movement of the lower abdominal wall, abdominal bracing, pelvic tilting, and inward movement of the lower and upper abdominal wall. Inward movement of the lower abdominal wall in supine produced greater activity of TrA compared to OI, OE and RA. During posterior pelvic tilting, middle OI was most active and with abdominal bracing, OE was predominately recruited. Regions of TrA were recruited differentially and an inverse relationship between lumbopelvic motion and TrA electromyography (EMG) was found. This study indicates that inward movement of the lower abdominal wall in supine produces the most independent activity of TrA relative to the other abdominal muscles, recruitment varies between regions of TrA, and observation of abdominal and lumbopelvic motion may assist in evaluation of exercise performance. r 2004 Elsevier Ltd. All rights reserved. Keywords: Exercises; Abdominal muscles; Transversus abdominis; Low back pain

1. Introduction A diverse range of exercises is used clinically to retrain the trunk muscles. However, recruitment of the abdominal muscles during exercises that aim to restore motor control have not been clearly defined. Most studies have used surface electromyography (EMG) to investigate these techniques (Partridge and Walters, 1960; Kennedy, 1980; Richardson et al., 1990; Jull et al., 1995; Allison et al., 1998; O’Sullivan et al., 1998; Vezina and HubleyKozey, 2000) and the results of the small number of intramuscular EMG studies are inconclusive (Carman Corresponding author. Tel.: +61 3 9903 0590; fax: +61 3 9903 0556. E-mail address: [email protected] (D.M. Urquhart).

1356-689X/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2004.08.011

et al., 1972; Strohl et al., 1981; Goldman et al., 1987; De Troyer et al., 1990). For example, three different recruitment patterns were reported when six subjects were instructed to ‘‘pull in’’ their abdominal wall (De Troyer et al., 1990). A contemporary approach for low back pain (LBP) involves recruitment of transversus abdominis (TrA) with minimal activity of the superficial abdominal muscles in the early stages of rehabilitation. This approach is based on evidence that activity of TrA contributes to spinal control (Cresswell et al., 1992; Hodges et al., 1999) and dysfunction of this muscle occurs in people with LBP (Hodges and Richardson, 1996b, 1998; Hodges, 2001). Although recruitment of TrA is emphasized initially, all of the trunk muscles are considered to be important for the restoration of normal function and progression involves strategies for

ARTICLE IN PRESS D.M. Urquhart et al. / Manual Therapy 10 (2005) 144–153

re-education of the whole muscle system (Richardson et al., 1999). The efficacy of this method has been established in randomized control trials with acute and chronic LBP patients (Hides et al., 1996; O’Sullivan et al., 1997b,c). The technique involves inward movement of the lower abdominal wall without movement of the spine or pelvis (Richardson et al., 1999). Surface EMG studies indicate that activity of the superficial abdominal muscles is minimal during this manoeuvre (Jull et al., 1995), and indirect measurements of TrA activity with a pressure cuff under the abdomen to indicate movement of the abdominal wall, are related to direct EMG measures of TrA motor control (Hodges et al., 1996a). However, no study has directly investigated TrA activity during this, or other exercise approaches. Other exercise strategies have also been argued to be beneficial in LBP management. Abdominal bracing (lateral flaring of the abdominal wall) (Kennedy, 1980) and posterior pelvic tilting have been proposed to improve lumbopelvic control by elevation of intraabdominal pressure and by reduction of the lumbar lordosis, respectively (Kennedy, 1980; Vezina and Hubley-Kozey, 2000). However, there is controversy regarding the specific patterns of abdominal muscle recruitment during these exercises. A recent review concluded that muscle activation patterns during pelvic tilting are not clearly defined in people with or without LBP (Vezina et al., 1998). An additional consideration is that there are differences in the morphology and recruitment of regions of TrA and obliquus internus abdominis (OI) (Askar, 1977; Rizk, 1980; Hodges et al., 1999; Urquhart et al., 2001, 2004). Upper fascicles of TrA that attach to the rib cage are horizontal, and middle and lower fascicles that fuse with the thoracolumbar fascia and the iliac crest are inferomedial (Urquhart et al., 2001). Fibres of upper TrA are also active with the opposite direction of trunk rotation to lower and middle fibres (Urquhart et al., 2004), and activity of lower and upper fibres of OI vary during posterior pelvic tilting (Carman et al., 1972). Although these reports suggest regional differences in activity of the abdominal muscles, their recruitment has not been comprehensively investigated during voluntary exercises. The aims of this study were to investigate recruitment of regions of the abdominal muscles during exercises used in LBP management, and to determine if common clinical techniques, such as observation of abdominal, spinal and pelvic motion, assist differentiation of patterns of abdominal muscle recruitment. 2. Methods 2.1. Subjects Seven subjects (4 male, 3 female), with a mean (SD) age, height, and weight of 30(4) years, 174(9) cm, and

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68(15) kg, participated in the study. Subjects were excluded if they had a history of low back or leg pain that affected function in the preceding 2 years, or any abdominal, gastrointestinal, neurological or respiratory condition. All subjects had an ‘average’ activity level, as determined by the habitual physical activity questionnaire (Baecke et al., 1982). Five subjects had performed the exercises previously and all subjects were involved in another study (Urquhart et al., 2004). All procedures were approved by the institutional research ethics committee and conducted in accordance with the declaration of Helsinki. 2.2. Electromyography Recordings of EMG were made using bipolar finewire electrodes inserted into three regions of the abdominal wall under the guidance of real-time ultrasound imaging (5 MHz curved array transducer) (128XP/4, Acuson, Mountain View, CA). Electrodes were fabricated from two strands of Teflon-coated stainless steel wire (75 mm) (A-M Systems Inc., Everett, Washington, USA), with 1 mm of Teflon removed from the ends. The electrodes were threaded into a hypodermic needle (0.70
38 mm) and the tips bent back 1–2 mm to form hooks. Electrodes were inserted into the upper region of TrA (adjacent to the 8th rib), the middle region of TrA, OI and obliquus externus abdominis (OE) (midway between the iliac crest and inferior border of the rib cage), and the lower region of TrA and OI (adjacent to the anterior superior iliac spine (ASIS)) (De Troyer et al., 1990; Cresswell et al., 1992; Hodges and Richardson, 1997; Urquhart et al., 2004). Pairs of surface EMG electrodes (Ag/AgCl discs, 1 cm diameter and 2 cm inter-electrode distance) were placed over rectus abdominis (RA), halfway between the umbilicus and the pubic symphysis. A ground electrode was placed on the iliac crest. EMG data were bandpass filtered between 50 Hz and 1 kHz and sampled at 2 kHz using a Power1401 data acquisition system and Spike2 software (Cambridge Electronic Design, Cambridge, UK). The data was exported and analysed using Matlab 6 (release 12; MathWorks, Natick, MA, USA). 2.3. Video motion analysis A video motion analysis system was used to quantify displacement of the upper, middle and lower regions of the abdominal wall and movement of the lumbar spine and pelvis in prone. Data were captured with a digital video camera (Sony DCR TRV20, Tokyo, Japan), positioned 2 m away and perpendicular to the subject. A diffuse light source, placed under the subject’s abdomen, and a black background were used to highlight the edge of the abdominal wall in the video image (Fig. 1). A marker was placed on the spinous

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process of the L3 vertebrae and the left ASIS to allow measurement of linear displacement of the lumbar spine and pelvis. The border of the upper and middle abdominal regions (lower border of the rib cage), and the middle and lower abdominal regions (upper border of the iliac crest) were also identified. Video data were transferred to computer and edited using iMovie editing software (Apple Computer, Inc., Cupertino, CA). An edge detection program was written using Igor Pro (WaveMetrics Inc., Lake Oswego, USA) to measure displacement of the abdominal wall, and spine and pelvic motion was measured with NIH Image (National Institute of Health, Bethesda, MD, USA). Distances were calibrated to an object of known dimensions filmed in the same plane as the abdominal wall. Resolution was 0.5 mm. The motion parameters were found to be accurate and repeatable over a 24-h interval (ICC[2,1] =0.99) (Urquhart, 2002). 2.4. Procedure Subjects were positioned in prone with raised supports placed underneath the xiphisternum and pubic symphysis (Fig. 1). This allowed the edge of the anterior abdominal wall to be visible. The spine was positioned in neutral and the hips were flexed to 451. In separate trials, subjects were positioned in supine with similar lumbar spine, hip and knee positions. Subjects were trained by physiotherapists, experienced in exercise prescription for the abdominal abdominal regional markers

trigger (A)

(B)

light source

2.5. Data processing

spine marker LED

black background

muscles, to perform four manoeuvres using standard instructions (Table 1); inward movement of the lower abdominal wall (Richardson et al., 1999), abdominal bracing (flaring of the lateral and anterior abdominal wall) (Kennedy, 1965, 1980), posterior pelvic tilting (posterior rotation of the pelvis), and combined inward movement of the lower and upper abdominal wall. Contemporary exercise interventions focus on low level contractions (Richardson et al., 1999), which is consistent with evidence that suggests low effort is sufficient to provide muscle stiffness required for joint control (Hoffer and Andreassen, 1981; Cholewicki and McGill, 1996). Thus, each task was performed with ‘‘mild’’ effort, which is equivalent to a rating of 2 on the Borg scale (Borg, 1982). Subjects were trained with instruction and verbal and tactile feedback until they were able to perform the manoeuvres correctly. Three repetitions were performed and the order of tasks was randomized. A trigger was activated by the subject to signal when they were relaxed (baseline) and had performed the task. Maximum voluntary isometric trunk flexion, ipsilateral and contralateral trunk rotation, and a maximal valsalva and forced expiratory manoeuvre were performed in supine for normalization of RA, OI, OE and TrA EMG, respectively (Hodges et al., 1999). The peak activity of each muscle across these tasks was selected for normalization. A submaximal isometric manoeuvre was performed as an alternative task for EMG normalization and involved elevation of both legs so that the heels were 5 cm from the supporting surface.

ASIS marker

electrode insertion sites

Fig. 1. Experimental set-up. Subjects were positioned in prone with supports underneath the xiphisternum and pubic symphysis (A), and in supine with their hips flexed to 451 (B). A marker was placed on the spinous process of the L3 vertebrae and the left ASIS, and borders of the abdominal regions were marked. A black background was used and a light source was placed inferior to the abdominal wall.

The root mean square (RMS) EMG amplitude was calculated for 2 s at baseline and for 2 s during the manoeuvre (at the time indicated by the trigger). The mean displacement of the upper, middle and lower regions of the abdominal wall, and the motion of the spine and pelvis in the vertical and horizontal planes was also determined for these periods. EMG activity recorded during the maximal and submaximal tasks was used to normalize the RMS EMG amplitude. Although reduced variance has been reported with normalization of surface EMG recordings to a submaximal task (Allison et al., 1998), maximal efforts have been considered to provide more meaningful values for interpretation (Andersson et al., 1998; Burden and Bartlett, 1999). 2.6. Statistical analysis A two-way repeated-measures ANOVA was used to compare activity between exercise tasks and between muscles/regions. Duncan’s multiple-range test was used for post-hoc analysis. To examine the association between EMG activity of the abdominal muscles and

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Table 1 Standardized instructions used for the voluntary exercises Exercise

Instructionsa

Inward movement of the lower abdominal wall

Breathe in and out. Gently and slowly draw in your lower abdomen below your navel without moving your upper stomach, back or pelvis.

Inward movement of the lower and upper abdominal wall

Breathe in and out. Gently and slowly draw in your lower and upper abdomen without moving your back or pelvis.

Abdominal bracing

Breathe in and out. Gently and slowly swell out your waist without drawing your abdomen inwards or moving your back or pelvis.

Posterior pelvic tilting

Breathe in and out. Gently and slowly rock your pelvis backwards.

a

Subjects were also instructed to perform each exercise with ‘mild’ effort (a rating of 2 on the Borg scale).

Table 2 Standard deviation data for the RMS EMG amplitude of the abdominal muscles normalized to maximal (Mx) and submaximal (SMx) isometric voluntary contractions and results of the Fmax test (F) for comparison of the variance between these normalization techniques Muscle/region

Abdominal exercise Lower (supine)

LTrA MTrA UTrA LOI MOI OE RA

Mx 0.05 0.05 0.02 0.03 0.03 0.005 0.02

SMx 3.21 0.67 0.37 2.13 0.09 0.05 0.02

Pelvic tilting F S S S S NS S NS

Mx 0.02 0.02 0.003 0.005 0.02 0.03 0.02

SMx 1.00 3.67 0.02 0.11 0.11 0.15 0.06

Bracing F S S S S S S NS

Mx 0.03 0.01 0.01 0.01 0.02 0.03 0.02

Lower (prone) SMx 1.25 1.59 0.29 0.21 0.21 0.04 0.05

F S S S S S NS NS

Mx 0.04 0.02 0.001 0.004 0.06 0.06 0.01

SMx 0.78 3.68 0.01 0.20 0.45 0.26 0.02

Lower/upper F S S S S S S NS

Mx 0.03 0.01 0.03 0.02 0.05 0.07 0.04

SMx 3.00 1.78 0.19 0.43 0.47 0.07 0.10

F S S S S S NS NS

L—lower; M—middle; U—upper; Lower (supine)—inward movement of the lower abdominal wall in supine; pelvic tilting—posterior tilting of the pelvis; bracing—abdominal bracing; lower (prone)—inward movement of the lower abdominal in prone; lower/upper—inward movement of the lower and upper abdominal wall; NS—non-significant; S—significant (Po0.05).

abdominal, spinal and pelvic motion, Pearson productmoment correlations were calculated. The Fmax statistic was used to investigate differences in variance between the mean RMS EMG for each muscle normalized to a maximal and submaximal task (Winer et al., 1991). Statistical significance was set at 0.05.

3. Results 3.1. EMG normalization Prior to analysis of the abdominal tasks, the maximal and submaximal EMG normalization methods were compared. There was greater variability in the mean RMS EMG amplitude with normalization to the submaximal procedure for all muscles except RA (Table 2). The standard deviations for the RMS EMG of lower and middle TrA were up to 180 times greater compared to the maximal normalization. Therefore, the intramuscular EMG data was normalized to EMG activity recorded during the maximal manoeuvre.

3.2. Comparison of abdominal muscle recruitment for each exercise There were differences in recruitment between the abdominal muscles during inward movement of the lower abdominal wall in supine, abdominal bracing and pelvic tilting (Po0.001) (Fig. 2A). In contrast, no difference between the abdominal muscles was observed with inward movement of the lower abdominal wall in prone (P40.05) and combined inward movement of the lower and upper abdominal wall (P40.009). During inward movement of the lower abdominal wall in supine, TrA EMG was 70%, 100% and 65% greater than that of OI, OE and RA, respectively (Po0.01). Minimal activity of OI, OE and RA (1.3%, 0.9%, 1.8%) was also observed for one subject. There were regional differences in TrA recruitment. Mean RMS EMG amplitude of the upper region was approximately half that of the lower and middle regions (Po0.001). In contrast, OI EMG was less than lower and middle TrA (Po0.02), but similar to RA and OE (P40.07). In addition, no difference in OI EMG was

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Fig. 2. RMS EMG amplitude of abdominal muscles/regions during different exercise conditions (normalized to a maximal voluntary contraction). Mean (SD) RMS EMG of lower and middle TrA and OI, and upper TrA, OE and RA during inward movement of the lower abdominal wall (supine (lower supine) and prone (lower prone)), bracing, posterior tilting of the pelvis (pelvic tilting) and combined inward movement of the lower and upper abdominal wall (lower/upper). Note the greater and more independent activity of TrA in supine compared to prone. Similarities in activation of the lower and middle regions of TrA, contrast with differences in activation of the upper region of the muscle. The standard deviations are large indicating variability in abdominal muscle recruitment between subjects.  Po0.05.

identified between regions of the muscle (P ¼ 0:3). Mean OE RMS EMG was negative, indicating reduction in activity from baseline. With abdominal bracing, OE EMG was greater than that of upper TrA, lower OI, and RA (Po0.05). There was minimal activity of upper TrA, and although there was a trend for differences in the EMG activity of

regions of TrA, this was not significant (lower TrA: P ¼ 0:07; middle TrA: P ¼ 0:051). There was also similar activity of the lower and middle OI during abdominal bracing (P ¼ 0:09). When subjects tilted their pelvis posteriorly, middle OI had greater activity compared to RA (P ¼ 0:03) and upper TrA (P ¼ 0:01). In contrast, there was no

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difference between the abdominal muscles during inward movement of the lower abdominal wall (P40.05), and the lower and upper abdominal wall in prone (P40.09). However, there was a trend towards greater TrA activity compared to the other abdominal muscles. 3.3. Comparison of abdominal muscle recruitment between exercises Recruitment of lower and middle TrA, and OE differed between the exercise conditions (Po0.001) (Fig. 2B). Lower and middle TrA EMG was greater during inward movement of the lower abdominal wall in supine than other tasks (Po0.05). In contrast, OE EMG was greater during abdominal bracing than the other techniques (except pelvic tilting) (Po0.05). Activity of lower and middle OI, RA and upper TrA was similar between exercises and between the supine and prone positions.

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pared to the other abdominal manoeuvres (Po0.001), and abdominal displacement with inward movement of the upper and lower abdominal wall was greater than abdominal bracing and inward movement of the lower abdominal wall in prone (Po0.002; Po0.001). The later two exercises did not differ in abdominal motion (P ¼ 0:5). Lumbar spine and pelvic motion was minimal and did not differ between tasks, with the exception of posterior pelvic tilting, in which greater spine and pelvic motion occurred (Po0.001) (Fig. 4). There was a high correlation between movement of the lumbar spine and pelvis (r ¼ 0:9), and a significant negative correlation between lumbopelvic motion and TrA EMG (as a proportion of total activity) was found (r ¼ 0:6) (Fig. 5). Although there was no significant correlation between displacement of the lumbopelvic region and OI and RA EMG, there was a positive correlation between OE EMG and lumbopelvic motion. In addition, there was a low to moderate correlation between movement of the abdominal wall and TrA EMG (r ¼ 0:4; Po0.05) (Fig. 5).

3.4. Movement of the abdominal wall, spine and pelvis Abdominal wall displacement differed between tasks (Po0.001), but not between the upper, middle and lower abdominal regions (P ¼ 0:1) (Fig. 3). Greater abdominal motion occurred during pelvic tilting com-

Mean abdominal displacement (mm)

Spinal displacement (mm)

*

20 16

*

* 7.0

*

12 8

5.0 4.0 3.0 2.0 1.0 lower

(A)

0 lower

lower/upper

bracing

upper middle lower

0.6 0.5 0.4 0.3 0.2 0.1 0 lower

lower/upper

bracing

pelvic tilting

Fig. 3. Displacement of regions of the abdominal wall. Abdominal displacement expressed as the mean (SD) of absolute movement (A) and the mean expressed as a proportion of the total abdominal movement (B) during inward movement of the lower abdominal wall in prone (lower), pelvic tilting, abdominal bracing, and combined inward movement of the lower and upper abdominal wall (lower/ upper). Note the differences in abdominal displacement between the exercise conditions. Po0.05.

lower/upper

bracing

*

pelvic tilting 5.0 Pelvic displacement (mm)

Regional proportion of abdominal displacement (B)

*

6.0

0

4

(A)

*

*

4.0 3.0 2.0 1.0 0

(B)

*

pelvic tilting

lower

lower/upper bracing

pelvic tilting

Fig. 4. Mean (SD) displacement of the lumbar spine and pelvis. Movement of the lumbar spine (A) and pelvis (B) during inward movement of the lower abdominal wall in prone (lower), pelvic tilting, abdominal bracing, and combined inward movement of the lower and upper abdominal wall (lower/upper). Note greater movement of the pelvis and spine during posterior pelvic tilting.  Po0.05.

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when data were normalized to maximal manoeuvres rather than submaximal tasks. Although this contrasts with a previous study (Allison et al., 1998), the differences may be explained by the use of surface EMG in that investigation.

TrA EMG activity (increase)

1.2

0.8

4.2. Inward movement of the lower abdominal wall in supine

0.4

The results suggest that recruitment of TrA with minimal activity of other abdominal muscles may be best achieved during inward movement of the lower abdominal wall. These findings agree with reports that TrA is most consistently active during a ‘‘belly in’’ manoeuvre (Strohl et al., 1981; Goldman et al., 1987; De Troyer et al., 1990), and that minimal superficial abdominal muscle activity occurs during this task (Jull et al., 1995; Richardson et al., 1995). The results are also consistent with an exercise approach for the management of LBP, which involves retraining the activity of TrA to be independent of the other abdominal muscles (Richardson et al., 1999). Three randomised control trials of different subgroups have reported improvements in pain and function with exercise interventions that involve inward movement of the lower abdomen (Hides et al., 1996; O’Sullivan et al., 1997b,c). These outcomes have been hypothesized to result from improved motor control of TrA (and multifidus). Each of these studies involved training in a variety of positions, including supine (O’Sullivan et al., 1997b,c) and standing (Hides et al., 1996) in the early stages of rehabilitation, and during functional activities as exercise retraining was progressed (Hides et al., 1996; O’Sullivan et al., 1997b,c). Although it is unlikely that the improvements were solely due to changes in TrA function, this is the common feature of the interventions. As the results of the present study suggest that the ability to activate TrA may vary between positions and it cannot be confirmed that the same manoeuvre examined in the current study was implemented, further research is required to determine whether TrA activity can be changed with this intervention. Activation of TrA with minimal superficial abdominal muscle activity has been argued to be an important feature of inward movement of the lower abdominal wall. In this study mean EMG activity of these muscles was considerably less than that of TrA. In addition, minimal activity of OI, OE and RA in one subject suggests that it may be possible to activate TrA almost independently from the other abdominal muscles, at least with training during this task. There was no difference between OI, OE and RA during inward movement of the lower abdominal wall in supine. However, the slightly greater activity of OI may have reached significance with a greater number of

0.7 Ab 0.5 do mi na 0.3 (in l di cre spl as ace e) m en t

0.7 3.3

0.1

6.0

tion mo e) c i s v l Pe ecrea (d

Fig. 5. Association between EMG activity, abdominal displacement and lumbopelvic motion. A three-dimensional graph depicting the relationship between EMG activity of all regions of TrA (as a proportion of the total abdominal muscle activity) (y axis), maximal abdominal displacement (x axis), and pelvic motion (z axis). EMG activity of TrA, relative to the other abdominal muscles, was greater when abdominal movement was performed without pelvic motion.

4. Discussion This study presents several important findings. First, there were distinct patterns of abdominal muscle recruitment between exercise tasks. Notably, the greatest and most independent activity of TrA was recorded with inward movement of the lower abdominal wall in supine. Second, abdominal muscle activity was dependent on body position, with differential activity of TrA evident in supine, but not in prone. Third, there were regional differences in the recruitment of TrA, with greater activity of the lower and middle regions of TrA compared to the upper region. Finally, activity of TrA was greater relative to the other abdominal muscles when lumbopelvic motion was limited. These results have important implications for selection of exercise techniques, positions and strategies for assessment and retraining of abdominal muscle function. 4.1. Methodological issues Two methodological issues require consideration. Firstly, due to the invasive nature of the study only seven subjects were recruited. Although this number is relatively consistent with previous intramuscular EMG investigations, it is important to consider that this may limit the statistical power of the study. Second, data in this study were normalized to maximal voluntary contractions. Variability in the present study was less

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subjects. Dowd (1992) reported similar findings using intramuscular EMG but did not record from TrA. In contrast, surface EMG studies have reported greater activity of OI and/or OE relative to RA (O’Sullivan et al., 1997a; Vezina and Hubley-Kozey, 2000). These differences may be explained by cross-talk from deeper and adjacent muscles, possibly resulting in overestimation of the superficial muscle activity. There were regional differences in TrA recruitment during inward movement of the lower abdominal wall in supine. This is a novel finding. Although activity of upper and lower/middle TrA varies during trunk rotation (Urquhart et al., 2004) and repetitive limb movements (Hodges et al., 1999), no studies have identified regional differences during voluntary manoeuvres. 4.3. Inward movement of the lower abdominal wall in prone Unlike supine, there was no differentiation in abdominal muscle activity with inward movement of the lower abdominal wall in prone. This is consistent with previous studies that report differences in abdominal muscle activity between positions (Carman et al., 1972; Richardson et al., 1992). This may be due to the greater gravitational demand in prone, or reflexmediated activity of the superficial muscles in response to stretch. In addition, an individual’s internal body representation has been shown to vary with the relative position of body segments, which may influence movement performance (Gurfinkel, 1994). The absence of differentiation of abdominal muscle activity in prone is not consistent with the use of this position for evaluation of TrA activity in clinical practice (Richardson et al., 1999). Although this technique is widely referenced and the position used in this study differs in several characteristics to the clinical test (e.g. abdominal support), assessment in supine may be more optimal for future clinical and laboratory work. 4.4. Abdominal bracing Identification of greater OE activity than the other abdominal muscles with abdominal bracing differs from previous reports which indicate greater RA activity compared to the anterolateral abdominals (Richardson et al., 1995), and no difference between muscles (Allison et al., 1998). However, the results suggest that bracing would not be appropriate if the aim of the exercise is to preferentially activate TrA or OI. 4.5. Posterior pelvic tilt Similar to our data, Partridge and Walters (1960) reported greater activity of OI than RA and OE with

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posterior pelvic tilt. However, other studies have found greater RA activity compared to the anterolateral abdominals (Richardson et al., 1995), and greater activity of OE than RA (Vezina and Hubley-Kozey, 2000). In addition, similar activity of OI and RA has been observed during this manoeuvre (Flint and Gudgell, 1965; Carman et al., 1972). Although these varying results may have been due to differences in the task, electrode placement or EMG normalization technique, they also provide evidence that body position may contribute to differences in abdominal muscle recruitment. 4.6. Comparison of abdominal muscle recruitment between exercises In contrast to OI and RA, activity of TrA and OE differed between the tasks, with greater activity during inward movement of the abdominal wall and pelvic tilting, respectively. This is consistent with previous reports of greater OE EMG activity during posterior tilting of the pelvis compared to ‘abdominal hollowing’ (drawing your navel up and in towards your spine) (Vezina and Hubley-Kozey, 2000). However, activity of RA (Vezina and Hubley-Kozey, 2000) and the ‘oblique abdominals’ (Richardson et al., 1992) has also been reported to vary between these manoeuvres. Differences between studies may be due to variation in the level of effort. It is important to note that activity of lower OI followed a similar pattern to that of TrA. Although there was no difference in OI activity between the exercises, this may have been due to insufficient statistical power that resulted from the small number of subjects used in this invasive study. 4.7. Abdominal, lumbar spine and pelvic movement Although abdominal wall movement differed between the tasks, there was no variation in the displacement between regions of the abdominal wall. This may be due to the small size of the displacement. However, there was trend towards greater movement of the lower region during inward movement of the lower abdominal wall. This finding is consistent with clinical observations (Richardson et al., 1999). Recruitment of TrA and the combined activity of OI, OE and RA (as a proportion of total abdominal muscle activity) was found to vary linearly with the amplitude of lumbar spine and pelvic displacement. This is consistent with clinical hypotheses and indicates that activation of TrA is more independent if there is no pelvis or spinal motion (Richardson et al., 1999). There was also a trend for TrA EMG to be related to abdominal wall movement. This agrees with previous reports of a relationship between pressure change (as measured with an air-filled cuff) associated with inward

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displacement of the abdominal wall, and function of TrA, recorded as EMG onsets associated with arm movement (Hodges et al., 1996a). Thus, TrA is more likely to represent a greater proportion of total abdominal activity when abdominal movement occurs with limited lumbopelvic motion. 4.8. Clinical implications This study has implications for abdominal muscle retraining in clinical practice. The results provide further evidence to validate inward movement of the lower abdominal wall in the rehabilitation of TrA in LBP patients. The findings may also assist in selection of exercises for assessment and retraining of the other abdominal muscles. For instance, pelvic tilting is likely to produce greater activity of middle OI relative to upper TrA and RA, and abdominal bracing recruits OE with less activity of upper TrA, lower OI and RA. In addition, incorrect strategies used to mimic the required task may also be identified. To activate TrA independently from the other abdominal muscles, it would be important to discourage movement of the upper abdomen, bracing of the abdominal wall, or posterior tilting of the pelvis. These results also emphasize the importance of observation for assessment of muscle function. For instance, motion of the abdominal wall and lumbopelvic region may assist in the determination of the muscle recruitment strategy. Furthermore, these results indicate that abdominal muscle recruitment may be influenced by patient positioning. Differential recruitment of TrA may be improved in supine compared to prone, indicating that assessment and re-education of abdominal muscle function in a range of positions should be considered. However, further research is required to determine whether similar strategies are used by people with LBP and to develop improved strategies for restoration of motor control.

Acknowledgments This work was supported by the Australian Physiotherapy Association (Victorian Branch) and the National Health and Medical Research Council. The authors wish to thank Lorimer Moseley for his assistance with data collection and Beryl Kennedy for discussions on methodology.

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Richardson CA, Jull G, Toppenberg R, Comerford M. Techniques for active lumbar stabilisation for spinal protection: A pilot study. Australian Journal of Physiotherapy 1992;38(2):105–12. Richardson CA, Jull GA, Richardson BA. A dysfunction of the deep abdominal muscles exists in low back pain patients. In: Proceedings of World Confederation of Physical Therapists, Washington DC, 1995. p. 932. Richardson CA, Jull GA, Hodges PW, Hides JA. Therapeutic exercise for spinal segmental stabilization in low back pain: Scientific basis and clinical approach. London: Churchill Livingstone; 1999. Rizk NN. A new description of the anterior abdominal wall in man and mammals. Journal of Anatomy 1980;131(3):373–85. Strohl KP, Mead J, Banzett RB, Loring SH, Kosch PC. Regional differences in abdominal muscle activity during various maneuvers in humans. Journal of Applied Physiology 1981;51(6):1471–6. Urquhart DM, Barker PJ, Hodges PW, Story IH, Briggs CA. Regional morphology of transversus abdominis and internal oblique. In: Proceedings of the Musculoskeletal Physiotherapy Australia Twelfth Biennial Conference, Adelaide, Australia, 2001. Urquhart DM, Hodges PW, Story IH. Regional recruitment of transversus abdominis in trunk rotation. European Spine Journal 2004; p. 35. Urquhart, DM. Regional variation in morphology and recruitment of the abdominal muscles: Implications for control and movement of the lumbar spine and pelvis. PhD Thesis, School of Physiotherapy, The University of Melbourne, 2002. Vezina MJ, Hubley-Kozey CL, Egan DA. A review of the muscle activation patterns associated with the pelvic tilt exercise used in the treatment of low back pain. The Journal of Manual and Manipulative Therapy 1998;6(4):191–201. Vezina MJ, Hubley-Kozey CL. Muscle activation in therapeutic exercises to improve trunk stability. Archives of Physical Medicine and Rehabilitation 2000;81(10):1370–9. Winer BJ, Brown DR, Michels KM. Statistical principles in experimental design, 3rd ed. New York: McGraw-Hill; 1991.

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Professional issue

Is it time to stop functional pre-manipulation testing of the cervical spine? Haymo Thiel, George Rix Anglo-European College of Chiropractic, 13-15 Parkwood Road, Bournemouth BH5 2DF, UK Received 19 September 2003; received in revised form 2 April 2004; accepted 30 June 2004

Abstract The combined extended and rotated cervical spine position has been postulated to affect vertebral artery blood flow by primarily causing a narrowing of the vessel lumen, usually within the artery contralateral to the side of head rotation. The production of brainstem symptoms during the manoeuvre has generally been considered to be a positive test result. As a consequence, functional pre-manipulation testing of the cervical spine has been part of clinical screening undertaken by chiropractors and other manual practitioners to rule out the risk of possible injury to the vertebral artery. To date, these testing procedures are taught to students and carried out in daily clinical practice, despite the considerable controversy that exists about their validity. This paper considers and discusses the usefulness of functional pre-manipulation testing for clinical scenarios, involving dissection, spasm or stenosis of the vertebral artery, and makes the following recommendations: (1) Practitioners must assess the patient thoroughly, through careful history taking and physical examination, for the possibility of vertebral artery dissection. It is important to note that vertebral artery dissection (VAD) may present as pain only, and may not be associated with symptoms and signs of brainstem ischaemia. (2) If there is a strong likelihood of VAD, provocative pre-manipulation tests should not be performed, and the patient must be referred appropriately. (3) In the patient presenting with symptoms of brainstem ischaemia due to non-dissection stenotic vertebral artery pathologies, provocative testing is very unlikely to provide any useful additional diagnostic information. (4) In the patient with unapparent vertebral artery pathology, where spinal manipulative therapy (SMT) is considered as the treatment of choice, provocative testing is very unlikely to provide any useful information in assessing the probability of manipulation induced vertebral artery injury. r 2004 Published by Elsevier Ltd.

Functional pre-manipulation testing of the cervical spine has been part of clinical screening undertaken by practitioners of spinal manipulative therapy (SMT) for many years, and various protocols have been adapted to rule out the risk of possible injury to the vertebral artery (Carey, 1995; Rivett, 1995; Grant, 1996; Barker et al., 2000). Since first reported in the literature in 1927 by DeKleyn and Nieuwenhuyse (DeKleyn and Nieuwenhuyse, 1927), the combined extended and rotated cervical spine position has been postulated to affect vertebral artery blood flow by primarily causing a narrowing of the vessel lumen, usually within the artery Corresponding author. Tel: +44-1202-436-317.

E-mail address: [email protected] (H. Thiel). 1356-689X/$ - see front matter r 2004 Published by Elsevier Ltd. doi:10.1016/j.math.2004.06.004

contralateral to the side of head rotation. The production of brainstem symptoms during the manoeuvre has generally been considered to be a positive test result. To date, these testing procedures are continued to be taught to students and carried out in daily clinical practice, despite the considerable controversy that exists about their validity (Kunnasmaa and Thiel, 1994; Thiel et al., 1994; Cote et al., 1996; Rivett et al., 1998; Licht et al., 2000; Westaway et al., 2003). This may be partially based on the belief that performance of these screening tests, and a negative result, could offer the practitioner some form of medico-legal or clinical negligence protection, or that these tests may afford, both the practitioner and the patient, a lesser risk of postmanipulation stroke.

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Clinical tests may have one or more of five functions (Table 1). Provocative or functional vertebral artery insufficiency tests are most commonly used for diagnostic or screening purposes. This commentary focuses on the role of functional vertebral artery insufficiency testing as a pre-manipulation screening tool. Clinical tests are used to perform a specific function for a specific condition, or risk factors for that condition, in a specific population (Lang and Secic, 1997). In this sense, the provocative or functional vertebral artery insufficiency tests are considered to be a screen for otherwise unapparent vertebral artery pathology that may represent a pre-manipulation risk, in a situation where SMT of the cervical spine is considered to be the treatment of choice. By ‘unapparent’ we mean the absence of historical or other clinical features suggestive of vessel pathology such as dissection, and/or brainstem ischaemia (Table 2). This scenario reflects the clinical situation that practitioners of SMT most commonly face with respect to pre-manipulation screening in their daily practice. In assessing the usefulness of a screening procedure, a prerequisite must be to define the pre-symptomatic condition that it is aimed at detecting. Although the exact pathophysiological mechanisms underlying stroke and SMT are still unclear, the most commonly accepted one is that of vertebral artery dissection (Frisoni and Anzola, 1991). If this dissection or other sequelae related to vessel wall injury was to be due to a pre-symptomatic congenital or acquired weakness of the vessel wall, it is hard to see how positional tests, aimed at assessing the haemodynamics of that still patent vessel, will afford any useful clinical information regarding the possible risk of injury. Furthermore, in this scenario, performing these tests alone may possibly put the patient at a higher risk due to the potential stretching forces exerted on an already weakened vessel wall. While obviously not in vivo, studies on human cadavers have shown that strain values exerted onto the vertebral artery during a premanipulation test are higher than those observed during a typical cervical SMT procedure (Symons et al., 2002). Although there are no documented cases of dissection following pre-manipulation testing alone, the literature cites many examples of non-manipulation positional

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manoeuvres of the head and neck that have been associated with cerebrovascular injury (Thiel, 1991; Rosner, 2003). Vessel spasm is another pathophysiological process that has been hypothesised by some to lead to vertebral artery occlusion following SMT (Easton and Sherman, 1977; Schmitt, 1991). This may occur with or without arterial wall damage. Again, and for the same reason as for dissection, it is hard to see how on biologically plausible grounds, a positional pre-manipulation test could assess for the possibility of an impending vasospasm. In summary, the construct validity of the tests with these pathologies in mind is poor. A less commonly accepted link between SMT and stroke is embolisation from a pre-existing thrombus formation in the vertebral artery. In the absence of endothelial injury, this pathological process is most commonly associated with atherosclerosis. The atheroma alone may result in an asymptomatic partial stenosis of the arterial lumen. Hypothetically, the addition of a test, which may further occlude the vessel, could result in sufficient alteration in arterial flow characteristics to produce ischaemic brainstem symptoms. On the other hand, it is also conceivable that the test may dislodge the embolus resulting in stroke. Hypoplasia of the vertebral arteries (p2 mm) has been considered another stenotic factor related to postmanipulation stroke (Mann and Refshauge, 2001). There is no evidence to suggest that a hypoplastic vessel has a greater predisposition to dissection. However, some reports suggest that in the event of vessel injury, a contralateral hypoplastic artery may not be able to provide sufficient collateral circulation to prevent ischaemia and possible infarction (Henderson and Cassidy, 1998; Mann and Refshauge, 2001). So what is the usefulness of the provocative or functional vertebral artery insufficiency tests in detecting lumenal stenosis due to thrombus or hypoplasia? In attempting to address this question only in vivo Doppler ultrasound studies of vertebral artery flow in human subjects have been reviewed. As mentioned previously, it is generally assumed that pre-manipulation positional manoeuvres measure the degree of lumenal patency, or absence thereof, via the production of transient brain-

Table 1 Functions of clinical tests A Screening test A Routine test A Diagnostic test A Staging test A Monitoring test

Performed on healthy asymptomatic people; used to identify those who are at risk of a specific disorder; outcome may justify a subsequent diagnostic test or direct preventative action; a good screening test has high sensitivity. Performed on symptomatic subjects; used as part of a battery of tests and may result in a ‘finding’ that is unrelated to the presenting condition. Performed on symptomatic subjects; used specifically either to identify the presence or absence of a disorder: a good diagnostic test has high specificity. Performed to quantify and characterise the nature or extent of a condition. Performed to track the progress of a condition over time.

Adapted from Lang and Secic (1997)

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Table 2 Clinical features of vertebral artery dissection and brainstem ischemia arising from vertebral artery insufficiency Historical and clinical features suggestive of vertebral artery dissection  Most common presenting symptoms are pain in the head and neck (in almost 90% of cases), often unilateral and sub-occipital  Patient often never experienced a similar pain before  Onset often acute, may be related to trauma or spontaneous. Distinction between traumatic and spontaneous quite arbitrary—spontaneous usually means no major trauma (RTA, fall). Detailed and careful history may reveal minor or trivial trauma (sports activities, painting the ceiling, sneezing). Searching for these things preceding the neck pain or headache may raise suspicion.  Pain has distinct, but non-specific features, intensity often severe and quality sharp  Patient may report a sensation of neck stiffness, but there is no limitation of ROM  Time delay between onset of symptoms and clinical features of brainstem ischaemia can range from hours to up to 14 days

Clinical features suggestive of brainstem ischaemia arising from vertebral artery insufficiency Major (most common) symptoms of vertebro-basilar insufficiency are:a  Dizziness/vertigo/giddiness/light headedness  Nausea (often with vomiting)  Numbness—most often unilateral facial; less commonly may involve trunk and limbs (contraversive or ipsiversive)  Ataxia/unsteadiness of gait is the most common  Diplopia,  (Patient may report limb weakness—uncommon feature)

Major (most common) neurological signs are:

        

Ipsilateral Horners syndrome Ipsilateral limb ataxia Gait ataxia Ipsilateral sensory abnormalities of face (CN V); most commonly a loss of pain and temperature (dissociated sensory loss); can get diminished/ absent ipsilateral corneal reflex Contraversive sensory abnormalities of trunk and limbs; most commonly dissociated (alternating analgesia) Ipsilateral cranial nerve IX–XII abnormalities Nystagmus; cerebellar or vestibular in origin Possible ipsilateral cranial nerve VII deficit Possible pyramidal signs; uncommon and often seen in isolation

Most clinical features arise from the territory of the posterior-inferior cerebellar artery (Wallenberg Syndrome) Adapted from Sturzenegger (1993) and Saeed et al. (2000) a Listed in descending order of frequency; data obtained from patients with dissection as the cause of vertebro-basilar insufficiency; symptoms are listed using the 5 D’s and 3 N’s framework.

stem ischaemic symptoms. In other words, the test is believed to be an indirect measure of vertebral artery haemodynamics. However, a review of the literature on vertebral artery flow studies clearly shows conflicting results with regard to the effects of sustained premanipulation positional manoeuvres. Doppler studies attempting to measure the volume, velocity, or resistance to contralateral vertebral artery flow, have inconsistently indicated either a decrease or disappearance in some of these flow parameters (Stevens, 1984, 1991; Refshauge, 1994; Haynes 1995, 1996, 2000, 2002; Licht et al., 1998; Rivett et al., 1999; Yi-Kai et al., 1999; Mitchell, 2003), or an insignificant or no change at all (Weingart and Bischoff, 1992; Thiel et al., 1994; Cote et al., 1996; Lantz et al., 1996; Licht et al., 1999; Zaina et al., 2003) when applying a variety of functional premanipulation tests. Further, there have been reports of patients who had either known vertebral artery hypoplasia or complete lumenal occlusion on neck rotation but did not experience any symptoms during the premanipulation manoeuvres (Bolton et al., 1989; Rivett et al., 1998; Westaway et al., 2003). Of particular interest

are the Doppler studies by Licht and his co-workers which seem to indicate that flow velocity in the vertebral artery is neither significantly affected shortly after SMT of the neck in asymptomatic subjects (Licht, 1998), nor in subjects who had tested positive on performing premanipulation tests (Licht et al., 2000). Even if one accepts that to an extent, the significant disparity of the results of the various studies on vertebral artery flow during functional pre-manipulation testing, is dependent upon a variety of methodological factors, the weight of the evidence seems to strongly suggest that these screening tests lack the necessary sensitivity in order to be valid and dependable predictors of risk. As such, a negative test result cannot determine the safety of cervical SMT. The lack of sensitivity of the pre-manipulation tests as a valid screening procedure is further supported by some of the findings of Haldeman et al. in their review of 64 medicolegal cases of cerebrovascular accidents associated with SMT of the cervical spine (Haldeman et al., 2002). In 27 of the cases, the practitioner had described the use of a pre-manipulation provocative screening manoeuvre,

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however, none of these patients had shown any adverse responses to this screening test before the manipulation. In view of these arguments, we would like to make the following observations and recommendations: 1. Practitioners must assess the patient thoroughly, through careful history taking and physical examination, for the possibility of vertebral artery dissection. It is important to note that VAD may present as pain only, and may not be associated with symptoms and signs of brainstem ischaemia (Table 2). 2. If there is a strong likelihood of VAD, provocative pre-manipulation tests should not be performed, and the patient must be referred appropriately. 3. In the patient presenting with symptoms of brainstem ischaemia due to non-dissection stenotic vertebral artery pathologies, provocative testing is very unlikely to provide any useful additional diagnostic information. 4. In the patient with unapparent vertebral artery pathology, where SMT is considered as the treatment of choice, provocative testing is very unlikely to provide any useful information in assessing the probability of manipulation induced vertebral artery injury. 5. Practitioners might well now consider whether provocative testing provides any real benefit to any of these patient populations.

References Barker S, Kesson M, Ashmore J, Turner G, Conway J, Stevens D. Guidance for pre-manipulative testing of the cervical spine. Manual Therapy 2000;5:37–40. Bolton P, Stick P, Lord R. Failure of clinical tests to predict cerebral ischemia before neck manipulation. Journal of Manipulative and Physiological Therapeutics 1989;12:304–7. Carey P. A suggested protocol for the examination and treatment of the cervical spine: managing the risk. Journal of the Canadian Chiropractice Association 1995;39:35–9. Cote P, Kreitz B, Cassidy D, Thiel H. The validity of the extensionrotation test as a clinical screening procedure before neck manipulation: a secondary analysis. Journal of Manipulative and Physiological Therapeutics 1996;19:159–64. DeKleyn A, Nieuwenhuyse P. Schwindelanfaelle und nystagmus bei einer bestimmten stellung des kopfes. Acta Otolaryngologica 1927;11:155–7. Easton J, Sherman D. Cervical manipulation and stroke. Stroke 1977;8:594–7. Frisoni G, Anzola G. Vertebrobasilar ischemia after neck motion. Stroke 1991;22:1452–60. Grant R. Vertebral artery testing—the Australian Physiotherapy Association protocol after 6 years. Manual Therapy 1996;1: 149–53. Haldeman S, Kohlbeck F, McGregor M. Unpredictability of cerebrovascular ischemia associated with cervical spine manipulation therapy. Spine 2002;27:49–55. Haynes M. Cervical rotational effects on vertebral artery flow. Chiropractice Journal of Australia 1995;25:73–6.

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Haynes M. Doppler studies comparing the effects of cervical rotation and lateral flexion on vertebral artery blood flow. Journal of Manipulative Physiological Therapeutics 1996;19:378–84. Haynes M. Vertebral arteries and neck rotation: Doppler velocimeter and duplex results compared. Ultrasound in Medicine and Biology 2000;26:57–62. Haynes M. Vertebral arteries and cervical movement: Doppler ultrasound velocimetry for screening before manipulation. Journal of Manipulative Physiological Therapeutics 2002;25:556–7. Henderson D, Cassidy D. Vertebral artery syndrome. Part A: vertebrobasilar vascular accidents associated with cervical manipulation. In: Vernon H editor. Upper cervical syndrome. Baltimore: Williams & Wilkins; 1998. p. 194–206. Kunnasmaa K, Thiel H. Vertebral artery syndrome: a review of the literature. Journal of Orthomolecular Medicine 1994;16: 17–20. Lang TA, Secic M. How to report statistics in medicine. Philadelphia: American College of Physicians; 1997. Lantz C, Bivius M, Pretorius D. The effect of extreme head positions on vertebral artery velocity. Bournemouth, UK: International Conference on Spinal Manipulation; 1996 p 197–19. Licht P. Vertebral artery flow and spinal manipulation: A randomized, controlled and observer-blinded study. Journal of Manipulative Physiological Therapeutics 1998;21:141–3. Licht P, Christensen H, Hoilund-Carlsen P. Vertebral artery volume flow in human beings. Journal of Manipulative Physiological Therapeutics 1999;22:363–7. Licht P, Christensen H, Hoilund-Carlsen P. Is there a role for premanipulative testing before cervical manipulation? Journal of Manipulative and Physiological Therapeutics 2000;23:175–9. Licht P, Christensen H, Hojgaard P, Hoilund-Carlsen P. Triplex ultrasound of vertebral artery flow during cervical rotation. Journal of Manipulative Physiological Therapeutics 1998;21:27–31. Mann T, Refshauge K. Causes of complications from cervical spine manipulation. Australian Journal of Physiotherapy 2001;2001:255–66. Mitchell J. Changes in vertebral artery blood flow following normal rotation of the cervical spine. Journal of Manipulative Physiological Therapeutics 2003;26:347–51. Refshauge K. Rotation: a valid premanipulative dizziness test? Does it predict safe manipulation? Journal of Manipulative Physiological Therapeutics 1994;17:15–9. Rivett D. The pre-manipulative vertebral artery testing protocol: a brief review. New Zealand Journal of Physiotherapy 1995: 9–12. Rivett D, Milburn P, Chapple C. Negative pre-manipulative vertebral artery testing despite complete occlusion: a case of false negativity? Manual Therapy 1998;3:102–7. Rivett D, Sharples K, Milburn P. Effect of premanipulative tests on vertebral artery and internal carotid artery blood flow: a pilot study. Journal of Manipulative Physiological Therapeutics 1999;22:368–75. Rosner A. Risks of cerebrovascular accidents in perspective. Manuelle Medizin 2003;41:1–9. Schmitt H. Anatomical structure of the cervical spine with reference to pathology of manipulation complications. Manual Medicine 1991;6:93–101. Stevens A. Doppler sonography and neck rotation. Journal of Manual Medicine 1984;1:49–53. Stevens A. Functional Doppler sonography of the vertebral artery and some considerations about manual techniques. Journal of Manual Medicine 1991;6:102–5. Symons B, Leonard T, Herzog W. Internal forces sustained by the vertebral artery during spinal manipulative therapy. Journal of Manipulative Physiological Therapeutics 2002;25:504–10.

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Thiel H. Gross morphology and pathoanatomy of the vertebral arteries. Journal of Manipulative Physiological Therapeutics 1991;14:133–41. Thiel H, Wallace K, Donat J, Yong-Hing K. Effect of various head and neck positions on vertebral artery blood flow. Clinical Biomechanics 1994:105–10. Weingart J, Bischoff H. Doppler sonography of the vertebral artery with regard to head positions appropriate to manual medicine. Journal of Manual Medicine 1992;6:62–5. Westaway M, Stratford P, Symons B. False-negative extension/rotation pre-manipulative screening test on a patient

with an atretic and hypoplastic vertebral artery. Manual Therapy 2003;8:120–7. Yi-Kai L, Yun-Kun Z, Cai-Mo L, Shi-Zen Z. Changes and implications of blood flow velocity of the vertebral artery during rotation and extension of the head. Journal of Manipulative Physiological Therapies 1999;22:91–5. Zaina C, Grant R, Johnson C, Dansie J, Taylor P, Spyropolous P. The effect of cervical rotation on blood flow in the contralateral vertebral artery. Manual Therapy 2003;8: 103–9.

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Case report

A shoulder derangement Alessandro Ainaa, Stephen Mayb, a

Private Practitioner, Milano, Italy School of Physiotherapy, Faculty of Health and Well-Being, Sheffield Hallam University, UK

b

Received 5 May 2004; received in revised form 6 January 2005; accepted 11 January 2005

1. Introduction The McKenzie method of Mechanical Diagnosis and Therapy (McKenzie 1981, 1990; McKenzie and May, 2000, 2003) is well known and commonly applied in the management of spinal disorders (Foster et al., 1999; Gracey et al., 2002; Jackson, 2001). The system uses a mechanical evaluation involving end-range repeated movements performed whilst symptom and mechanical responses are monitored. The effect of the repeated movements is then used to classify patients in one of three mechanical syndromes: derangement, dysfunction, and postural syndrome. According to the classification different exercises and postural concepts are then used to reduce derangement, remodel dysfunction or correct adverse postural loads. The mechanical evaluation when used with spinal patients has demonstrated reliability amongst trained clinicians (Razmjou et al., 2000; Fritz et al., 2000; Kilpikoski et al., 2002), and prognostic validity (Long, 1995; Sufka et al., 1998; Werneke et al., 1999; Werneke and Hart, 2001). When McKenzie (1981) described his original concept he maintained that the system could equally well be applied to extremity problems. However there remained little evidence of clinicians using the system with nonspinal musculoskeletal problems, and more recently an explicit description of how the same principles could be applied to extremity problems was published (McKenzie and May, 2000). The purpose of this case report is to describe a new method of assessment and management, using the principles of Mechanical Diagnosis and Corresponding author. 219 Cemetery Road, Sheffield S11 8FQ,

UK. Tel./fax: +44 114 221 7303. E-mail address: [email protected] (S. May). 1356-689X/$ - see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2005.01.001

Therapy, as applied to a patient with a non-specific shoulder problem. This patient was classified and treated as having a derangement (Table 1) according to Mechanical Diagnosis and Therapy principles.

2. Case report 2.1. History A 38-year-old female physiotherapist attended the physiotherapy clinic with a complaint of right anterior shoulder pain, which had been present for 2 months. The condition had worsened in the last 2 weeks, when pain had radiated to her elbow and wrist (Fig. 1). Symptoms had started for no apparent reason with no trauma or overuse to the shoulder, and this was her first episode of a shoulder problem. Symptoms were intermittent and produced or aggravated by all movements of the shoulder, including movements at early range, and by sleeping on her right side. The shoulder and elbow were tender to the touch. Symptoms were made better or were absent when the shoulder was at rest and not moving. Functionally she was not aware of any limitations, although symptoms tended to get worse during the course of the day with normal work and domestic activities. She had had no previous or concurrent cervical symptoms. 2.2. Physical examination As a screening examination of the cervical spine revealed no restrictions of movement and no symptomatic or mechanical responses, involvement of the

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Table 1 Operational definitions for derangement syndrome (McKenzie and May 2000, 2003) Reducible derangement  Centralization: in response to therapeutic loading strategies pain is progressively abolished in a distal to proximal direction, and  each progressive abolition is retained over time,  until all symptoms are abolished, and  if local pain only is present this moves from a widespread to a more central location and then is abolished.  Or pain is decreased and then abolished during the application of therapeutic loading strategies.  The change in pain location, or decrease or abolition of pain remain better, and  should be accompanied or preceded by improvements in the mechanical presentation (range of movement and/or deformity).

Fig. 1. Body chart depicting pain presentation.

cervical spine was thought to be unlikely. Equally as movements of the shoulder so easily influenced symptoms involvement of the elbow or wrist was excluded and the examination focussed on shoulder movements and responses. An examination of single movements was conducted first to gain a baseline understanding of her shoulder’s symptomatic and mechanical presentations. She reported a dull ache around her anterior shoulder at rest. Flexion, extension, and adduction were full range and had no effect on her symptoms. Abduction was full range, but pain increased in her shoulder from 1501 to end-range. External rotation was limited to 701 and increased pain at end-range. The hand-behind-back position was limited at the buttock, also increased pain at end-range, and was the most symptomatic movement. Passive movements replicated active movements except range was somewhat larger, movement was prevented by the patient’s pain rather than a physical limitation; and hand-behind-back was again the most symptomatic movement. Resisted tests were equivocal, some being mildly uncomfortable, but no single test reproducing concordant symptoms. As hand-behind-back was the movement that most strongly affected the patient’s symptoms it was decided to explore this further in the repeated movement section

Fig. 2. Hand-behind-back with overpressure. The patient was instructed to put the affected arm behind the back, reach up as far as possible, and then with the other hand apply overpressure upwards.

of the examination. It was demonstrated to her how to perform this passively with assistance from the other hand, her baseline symptoms were recorded, and then she was asked to perform 10–15 repetitions. During the repetition of hand-behind-back she reported the movement to get easier and easier, and on observation the range increased. She was encouraged to push her right hand further up her back as it got easier and towards the end apply overpressure (Fig. 2). On completion of two sets of repetitions the patient reported no pain at rest; all symptoms had been abolished. On re-checking her baseline mechanical response abduction, external rotation and hand-behind-back were all full range and asymptomatic on movement.

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2.3. Conclusions

3. Discussion

Provisional diagnosis from the assessment was derangement of the shoulder. The self-treatment strategies for the next 24 h were 10–15 repetitions of hand-behindback with overpressure every 2 h, and to avoid sleeping on the right side, if possible. The patient was instructed to put the affected arm behind their back, reach up as far as possible, and then with the other hand apply overpressure to push the hand further up the back (Fig. 2).

Shoulder problems are frequently encountered in primary health care settings (Van der Windt et al., 1995; May, 2003). The long-term outcome is not always favourable and persisting symptoms or limitation of function is commonly reported (Croft et al., 1996). Various patho-anatomical mechanisms may give rise to shoulder symptoms, but the reliability of the examination process by which a diagnosis is reached has been shown to be weak (Liesdek et al., 1997; de Winter et al., 1999), and the diagnostic validity of certain tests to be only moderate (Calis et al., 2000). When treating patients with shoulder problems specific patho-anatomical diagnoses are frequently used (Van der Windt et al., 1995; Liesdek et al., 1997; de Winter et al., 1999), but the prevalence of non-specific symptoms at the shoulder has not been explored. The concept of non-specific musculoskeletal symptoms is well established in the field of low back pain (CSAG, 1994). McKenzie and May (2000) proposed the application of non-specific mechanical syndromes to extremity musculoskeletal problems. Although it was hypothesised that derangement related to internal disturbance of articular tissue, identification was not dependent on naming a specific patho-anatomical tissue. Identification instead depended upon symptomatic and mechanical responses to repeated end-range movements. In the derangement syndrome repeated end-range loading in the appropriate direction, termed directional preference, progressively decreases pain, with a simultaneous improvement in the range of motion (McKenzie and May, 2000). Likewise movements in the opposite direction may increase symptoms and limitations in the range of movement. The case report gives an example of such a response. The hypothetical model of derangement may assist in the education of the patient to obtain collaboration for self-management. Internal disturbance of articular tissue may be reduced by movements in one direction (in this instance hand-behind-back), and increased by opposite movements. The self-management advice to the patient comes directly from the findings at assessment: avoid the provocative movement and move repeatedly in the direction of preference. Clinical reasoning is the process by which the clinician, in discussion with the patient, proposes health management strategies based on clinical data, client choices and professional judgement and knowledge (Jones and Rivett, 2004). Hopefully it results in the best-judged action for individual patients and ‘wise’ action in the clinic (Jones and Rivett, 2004). Pattern recognition is part of this process, available to the expert in any field, when previous experience allows identification of a familiar phenomenon. In this instance the clinician recognised a favourable response to repeated

2.4. Day 2 The patient was seen again the following day. She reported she had performed her exercises regularly every 2 h, and demonstrated that she had been doing these accurately. She reported that she had had no pain in the last 24 h either on performing the exercise, at rest or with work or domestic activities. The shoulder and elbow were still slightly tender to the touch. On examination all shoulder movements were full range and pain free. Often in derangement one direction of movement, called the directional preference, decreases, abolishes or centralizes symptoms, whilst the opposite movement frequently exacerbates the symptomatic and mechanical presentations. The pathophysiological reason behind this clinical phenomenon is unknown. So to help confirm the diagnosis of derangement at the shoulder the patient was asked to perform repeated external rotation, which was the movement opposite to her directional preference. Pre-test she had no symptoms and no limitation of any movements. She then performed 10–15 end-range external rotation movements. These produced pain at her shoulder, elbow and wrist, which remained after cessation of the exercises, as well as producing limitation to her movements. Abduction was limited to 1501, external rotation 701 and handbehind-back limited at the waist. The patient was then asked to perform 10–15 repetitions of hand-behindback, following which all symptoms were abolished and all movements were once again full and pain free. The mechanical diagnosis of derangement was confirmed. The patient was advised to do 10–15 repetitions every 2–3 h for the next 5 days or if symptoms returned. 2.5. Follow-up Staff at the physiotherapy clinic contacted the patient 2 weeks later. She reported no further symptoms and full pain free movements and activities. However sleeping on the right shoulder was still uncomfortable. At a further telephone call 10 weeks later she remained pain free, with normal activity, and was now able to sleep on her right side with no problems.

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movements with the abolition of symptoms and an increase in range of movement—a response that fits the operational definition of derangement (Table 1). Pattern recognition in this instance rapidly provided an appropriate self-management strategy. The neck, an unlikely source of the patient’s symptoms as she reported the aggravating factor to be shoulder movements, was further discounted by a brief and uneventful examination. The obstructed shoulder movements and site of pain during the examination confirmed that the source of symptoms was the shoulder. Finally, repeated shoulder movements abolished the symptoms and increased the range of movement. Further examination was unnecessary at this point as the ‘best-judged action’ had been determined for this individual patient. Upon returning for review the patient reported a sustained improvement in symptoms and range. Furthermore, movements demonstrated an aggravation of the condition when repeated in the opposite direction to the directional preference. Derangement syndrome and directional preference was confirmed; thus discounting the need for further differential diagnosis or testing. From a theoretical perspective many structures could have been the source of this patient’s symptoms, including, but not only the intervertebral discs and zygapophyseal joints of the cervical spine, local somatic structures at the shoulder and elbow, and neurogenic structures, such as the radial nerve. The examination of this patient could have been elongated by an extended ‘search’ for the source of symptoms; notwithstanding that the battery of tests that might be used are of unproven validity and uncertain reliability (Liesdek et al., 1997; de Winter et al., 1999; Calis et al., 2000; Seffinger et al., 2004). Protracted examination with multiple tests of unproven worth does not signify expert clinical reasoning. Rather the reverse as more tests will generate more false-positive responses. It is not satisfactory simply to identify structures involved, as this alone does not provide sufficient information to understand the problem and its effect on the patient, nor is it sufficient to justify the course of management chosenyOf more concern is that solely tissue-based reasoning tends to promote inflexibility of management strategies. (Jones and Rivett, 2004, pp. 16–17) If the best ‘wise action’ for the patient has been determined by the physical examination, no further testing is needed to improve the management strategy, unless the presentation changes. The application of Mechanical Diagnosis and Therapy in the extremities is in its infancy. There are now numerous reports of the reliability and prognostic validity of the application of the McKenzie principles for spinal problems (McKenzie and May, 2003); the same evidence base needs to be created for non-spinal problems.

4. Conclusion This case report details the history and assessment of a woman who presented with non-specific shoulder pain. During the physical examination repeated movements were able to abolish her symptoms and restore a full range of pain free movement. Movements in the opposite direction reproduced symptoms and caused a painful restriction in her range. Such a symptom response is classified as a derangement under Mechanical Diagnosis and Therapy principles. The self-management strategy arose directly from the mechanical evaluation. This is the first documented evidence of the application of these principles to extremity problems.

References Calis M, Akgun K, Birtane M, Karacan I, Calis H, Tuzun F. Diagnostic values of clinical diagnostic tests in subacromial impingement syndrome. Annals of Rheumatic Disease 2000;59:44–7. Croft P, Pope D, Silman, et al. The clinical course of shoulder pain: prospective cohort study in primary care. British Medical Journal 1996;313:601–2. CSAG. Clinical standards advisory group—Low back pain. London: HMSO; 1994. De Winter AF, Jans MP, Scholten RJPM, Deville W, van Schaardenburg D, Bouter LM. Diagnostic classification of shoulder disorders: interobserver agreement and determinants of disagreement. Annals of Rheumatic Disease 1999;58:272–7. Foster NE, Thompson KA, Baxter GD, Allen JM. Management of nonspecific low back pain by physiotherapists in Britain and Ireland. A Descriptive Questionnaire of Current Clinical Practice Spine 1999;24:1332–42. Fritz JM, Delitto A, Vignovic M, Busse RG. Interrater reliability of judgements of the centralisation phenomenon and status change during movement testing in patients with low back pain. Archives of Physical Medicine and Rehabilitation 2000;81:57–61. Gracey JH, McDonough SM, Baxter GD. Physiotherapy management of low back pain. A survey of current practice in Northern Ireland. Spine 2002;27:406–11. Jackson DA. How is low back pain managed? Retrospective study of the first 200 patients with low back pain referred to a newly established community-based physiotherapy department physiotherapy 2001;87:573–81. Jones MA, Rivett DA. Introduction to clinical reasoning in manual therapy. In: Jones MA, Rivett DA, editors. Clinical Reasoning for Manual Therapists. Edinburgh: Butterworth Heinemann; 2004. p. 3–24 (Chapter 1). Kilpikoski S, Airaksinen O, Kankaanpaa M, Leminen P, Videman T, Alen M. Interexaminer reliability of low back pain assessment using the McKenzie method. Spine 2002;27:E207–14. Liesdek C, Van der Windt DA, Koes BW, Bouter LM. Soft-tissue disorders of the shoulder. Physiotherapy 1997;83:12–7. Long A. The Centralisation Phenomenon. Its usefulness as a predictor of outcome in conservative treatment of chronic low back pain. Spine 1995;20:2513–21. May S. An outcome audit for musculoskeletal patients in primary care. Physiotherapy Theory and Practice 2003;19:189–98. McKenzie RA. The lumbar spine. Mechanical diagnosis and therapy. New Zealand: Spinal Publications; 1981.

ARTICLE IN PRESS A. Aina, S. May / Manual Therapy 10 (2005) 159–163 McKenzie RA. The cervical and thoracic spine. Mechanical diagnosis and therapy. Spinal Publications (NZ) Ltd; 1990. McKenzie R, May S. The human extremities mechanical diagnosis and therapy. New Zealand: Spinal Publications Ltd; 2000. McKenzie R, May S. The lumbar spine mechanical diagnosis and therapy. 2nd ed. New Zealand: Spinal Publications Ltd; 2003. Razmjou H, Kramer JF, Yamada R. Intertester reliability of the McKenzie evaluation in assessing patients with mechanical lowback pain. Journal of Orthopaedic and Sports Physical Therapy 2000;30:368–89. Seffinger MA, Najm WI, Mishra SI, Adams A, Dickerson VM, Murphy LS, Reinsch S. Reliability of spinal palpation for diagnosis of back and neck pain. A systematic review of the literature. Spine 2004;29:E413–25.

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Sufka A, Hauger B, Trenary M, Bishop B, Hagen A, Lozon R, Martens B. Centralisation of low back pain and perceived functional outcome. Journal of Orthopaedic and Sports Physical Therapy 1998;27:205–12. Van der Windt DA, Koes BW, de Jong BA, Bouter LM. Shoulder disorders in general practice: incidence, patient characteristics, and management. Annals of Rheumatic Disease 1995;54:959–64. Werneke M, Hart DL, Cook D. A descriptive study of the centralisation phenomenon. A prospective analysis. Spine 1999;24:676–83. Werneke M, Hart DL. Centralization phenomenon as a prognostic factor for chronic pain or disability. Spine 2001;26:758–65.

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Manual Therapy 10 (2005) 164–171 www.elsevier.com/locate/math

Case report

Manipulation following regional interscalene anesthetic block for shoulder adhesive capsulitis: a case series$ Robert E. Boylesa,, Timothy W. Flynnb, Julie M. Whitmanc a

US Army-Baylor University Doctoral Program in Physical Therapy, AMEDDC & S, Fort Sam Houston, TX 78234, USA b Regis University, Denver, CO 80221, USA c Kirtland Air Force Base, Albuquerque, NM 87117, USA

1. Background and purpose Adhesive capsulitis (AC) of the glenohumeral (GH) joint, commonly known as ‘‘frozen shoulder’’, is a prevalent condition that is frequently treated by physical therapists (Dockrell and Wiseman, 1995; Holmes et al., 1997; van der Heijden et al., 1997; Winters et al., 1997; Connolly, 1998; Pearsall and Speer, 1998; Schwitalle et al., 1998; van der Windt et al., 1998; Siegel et al., 1999; Sandor, 2000; Vermeulen et al., 2000; Bentley and Tasto, 2001; Green et al., 2001). AC is more prevalent in women and in middle-aged individuals (Nevaiser, 1983, 1987; Siegel et al., 1999), in the diabetic patient population, with a rate of 2–5% in the non-diabetic population and 10–20% patients with non-insulindependent diabetes mellitus (Siegel et al., 1999; Carette, 2000; Bentley and Tasto, 2001). Patients with GH AC typically suffer from significant pain and progressively diminishing shoulder function (Nevaiser, 1983, 1987; Roubal et al., 1996; Placzek et al., 1998; Sandor, 2000). In a recent review on interventions for shoulder pain by the Cochrane Collaboration, Green et al. (2001), define AC as the presence of shoulder pain with restriction of passive and active GH motion. However, in their review of the literature, these same researchers found no standardized definitions for AC and reported conflicting criteria defining AC in the clinical trials reviewed. $ The views expressed in this case report are those of the authors and not the US Armed Services. Corresponding author. Tel.: +1-210-221-7387; fax: +1-210-2217585. E-mail address: [email protected] (R.E. Boyles).

1356-689X/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2004.08.002

The recommended course of treatment for patients with AC is highly variable (Schwitalle et al., 1998; Thomas et al., 1981; Nevaiser, 1983, 1987; Parker et al., 1989; Grubbs, 1993; Dockrell and Wiseman, 1995; Holmes et al., 1997; van der Heijden et al., 1997; Winters et al., 1997; Connolly, 1998; Harwood, 1998; Tukmachi, 1999; Griggs et al., 2000; Hannafin and Chiaia, 2000; Sandor, 2000; Bentley and Tasto, 2001; Green et al., 2001; Jerosch, 2001; Kivimaki and Pohjolainen, 2001; Omari and Bunker, 2001). In 1995, Dockrell and Wiseman (1995) randomly surveyed 100 patient records from ten out-patient physical therapy (PT) clinics in an effort to determine the ‘‘typical’’ PT treatment for patients with a primary diagnosis of shoulder AC. The majority of patients received eight to 18 treatments over a 2-month period of time. The most frequently utilized treatments included exercise (98%), manual GH mobilization (93%), and thermal modalities (60%). In a retrospective descriptive study evaluating the 10-year outcomes of a cohort of 50 patients, Miller et al. (1996) reported that many patients with AC will regain motion with minimal pain following a treatment program of home-based therapy, moist heat, NSAIDs, and physician-directed rehabilitation. Griggs et al. (2000) conducted a trial of clinic and home-based stretching exercises as a treatment for a cohort of 75 consecutive patients with AC. Although 85% of the patients reported satisfactory outcomes, significant differences still existed in pain and range of motion (ROM) when compared to the unaffected shoulder. Variables associated with unfavorable outcomes were a previous unsuccessful trial of PT and the presence of severe pain and functional limitations prior to the

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initiation of treatment. Two recent, large randomized clinical trials have compared PT treatments to steroid injection (Winters et al., 1997; van der Windt et al., 1998). Van der Windt et al. (1998) in a study of painful, stiff shoulders noted greater short-term improvements in pain and disability with injections versus a combined program of mobilization, exercise, and physical agents but no long-term differences (26th and 52nd weeks). In a similar study, Winters et al. (1997) compared treatments of physiotherapy (without mobilization/ manipulation), injection, and manipulation to the entire upper quarter for 198 patients with shoulder complaints. Of those patients thought to have symptoms primarily of GH etiology, patients receiving corticosteroid injections showed quicker recovery and higher patientperceived ‘‘cure’’ rates compared to patients receiving the other treatments. However, recurrence of pain by 11 weeks was highest in the injection group (18%), followed by physiotherapy (13%) and manipulation (8%). These trials appear to indicate that steroid injections are more helpful than conventional PT for short-term pain relief and improved disability scores, but this difference in benefit diminishes in the long-term. Manipulation under anesthesia (MUA) using longlever arm techniques in physiologic planes of motion, i.e. flexion, abduction, and rotations, has been described in the treatment for AC and is considered a last resort procedure for these patients (Neviaser, 1983, 1987; Grubbs, 1993; Connolly, 1998; Pearsall and Speer, 1998; Siegel et al., 1999). In this procedure, the clinician moves the patient’s shoulder through physiologic motions while the patient is under general anesthesia. Although positive post-manipulative clinical outcomes have been reported, potential complications associated with this long-lever arm technique include rotator cuff tears, humeral fractures, and brachial plexus injuries (Neviaser, 1983, 1987; Parker et al., 1989; Roubal et al., 1996; Connolly, 1998; Placzek et al., 1998; Sandor, 2000). In contrast to this technique, Roubal et al. (1996) and Placzek et al. (1998) have reported on a total of 39 patients treated with translational manipulations immediately following a regional interscalene brachial plexus anesthetic block. The technique utilized is purported to be safe and effective because smallamplitude, high-velocity, short-lever arm manipulations are employed rather than long-lever arm techniques (Roubal et al., 1996; Placzek et al., 1998). In both of these studies, marked improvements in shoulder ROM without complication were reported. Although Roubal et al. (1996) did not report long-term outcomes, favorable outcomes were reported at the 1-year followup for the 31 patients in the Placzek et al. (1998) study. Researchers in both studies concluded that manipulation can be an effective intervention for patients with AC and that this intervention should be considered by those practitioners skilled in joint manipulation.

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On the whole, it seems that some patients improve after a program of PT, steroid injections, and/or physician- or therapist-directed home care. However, some patients fail to respond to these approaches and continue to demonstrate residual passive range of motion (PROM) and functional losses in the long term (Shaffer et al., 1992). Therefore, some patients may elect for a manipulative approach in an attempt to improve the mobility and function of the affected shoulder. In this case series, the use of manipulation to the GH joint after an interscalene anesthetic block for patients with AC is described. In addition, the use of video fluoroscopy to assess GH joint arthrokinematics is presented.

2. Case description 2.1. Patient presentation The following four patients were referred to PT at Brooke Army Medical Center and Wilford Hall Air Force Medical Center, San Antonio, TX for management of shoulder disorders: Patient #1: A 47-year-old female nurse practitioner with a 7-month history of right shoulder pain, stiffness and inability to perform her normal activities of daily living. Referral diagnosis: AC. Patient #2: A 45-year-old female homemaker with an insidious onset, 6-month history of left shoulder pain and stiffness, sleep cycle disturbances, and inability to perform daily activities such as bathing, cleaning the house, and cooking. She particularly reported difficulty with overhead tasks such as washing her hair. This patient had already been treated with steroid injections with no reported improvements in mobility, function, or pain. Referral diagnosis: rotator cuff tear. Patient #3: A 56-year-old male computer programmer with a 7-month history of right shoulder pain, sleep cycle disturbance, and inability to put on his jacket or shirt without pain, reach across his desk, or use a computer mouse. Referral diagnosis: shoulder pain. Patient #4: A 66-year-old male retired army officer with a 10-month history of left shoulder pain, stiffness, and sleep cycle disturbance. Symptoms increased with shoulder elevation, reaching behind the back, and reaching across his body (horizontal adduction). This patient had already received steroid injections without relief of symptoms or improved shoulder function. Referral diagnosis: shoulder impingement. All patients had received prior PT interventions (shoulder joint mobilization, active and passive mobility exercise programs, strengthening exercises, and/or modalities) without satisfactory improvement in function or pain. Two had received prior steroid injections and two declined this treatment option.

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2.2. Baseline examination PROM measurements as well as the Shoulder Pain and Disability Index (SPADI) were used as outcome measures. PROM measurements were used because these measurements are important in the diagnosis of AC and are frequently used as an outcome measure in clinical research. All PROM measurements were performed as described by Norkin and White (1999). The SPADI is a 100-point, 13-item self-administered questionnaire designed to quantify shoulder pain and disability. Michener and Leggin (2001) reported a high test–retest reliability and internal consistency for the SPADI, while Williams et al. (1995) have shown that the instrument is responsive to change and accurately discriminates between patients who are improving or worsening. It is reported to have a moderately strong construct validity and more responsive to change than the Sickness Impact Profile (SIP), Heald and Riddle (1997). They also recommend the SPADI over the SIP for measuring the extent of disability in patients with shoulder problems. Additionally, a tenpoint change on the SPADI has been identified as the minimally clinically important change needed to be confident that a change has actually occurred (Heald and Riddle, 1997). The MRI reports for three patients (#2, #3, #4) demonstrated various degrees of rotator cuff tears. Physical examination findings for all four patients included the following: (1) markedly decreased ROM (flexion, abduction, and internal/external rotation); (2) essentially equal impairment in both active and passive shoulder motion; (3) pain at the end of each ROM; (4) capsular end-feels with passive GH joint mobility assessment. Based on patient history and the four physical examination findings listed above, the diagnostic clinical criteria for AC were standardized by all investigators. As part of the physical examination, Patients #1 and #4 had pre-manipulation video fluoroscopy studies. Anterior to posterior views were recorded on both extremities while the patient actively and repeatedly abducted the shoulder. The pre-manipulation study for both patients demonstrated a loss of normal arthrokinematics of the GH joint on the involved side. As described by Maitland (1999) and Levangie and Norkin (2001), the humeral head should glide inferiorly as the patient abducts the shoulder. In these two patients, the humeral head on the involved side failed to move caudally during physiological shoulder abduction. In fact, in both cases, the humeral head elevated with abduction. 2.3. Intervention As recommended by Placzek et al. (1998), patients were prescribed a 6-day Medrol Dosepak (Pharmacia

and Upjohn Company, Kalamazoo, MI, USA) by their referring physicians and started this medication the day before the manipulation. Patient #3 was not prescribed this medication because he is diabetic, a contraindication for taking the drug. After the patients signed the standard consent form utilized by the facility for all patients undergoing this procedure, an anesthesiologist performed a regional interscalene block on each patient. The blocks were found to last from 4 to 6 h. This procedure is described elsewhere (Roubal et al., 1996; Placzek et al., 1998). Patients then proceeded immediately to the out-patient PT clinic for treatment. A sling was used in transit to protect the patients’ anesthetized extremities. Immediately prior to the manipulation session, the patient’s shoulder PROM was recorded for flexion, abduction, and internal and external rotation. End-feels were also assessed to ensure that (1) the restrictions were still present after the extremity was anesthetized to ensure true AC and (2) to be sure that any increase in motion was a direct result of the manipulation and not the anesthesia. The reports by Placzek et al. (1998) and Roubal et al. (1996) describe manipulations that are performed only in two directions, anterior-to-posterior and superior-toinferior. In this case series, the physical therapists performed these same manipulations. Additionally, the therapists performed mobilization/manipulation in the directions of the remaining perceived joint restriction. To assess GH joint mobility, the therapists grasped the proximal humerus as close to the GH joint as possible and then glided the humeral head in anterior, posterior, caudal, and combined directions, in an attempt to detect joint hypomobility. This procedure was performed with the shoulder at various degrees of flexion, abduction, and internal/external rotation in an attempt to detect the position and direction of motion where proximal humeral translation was the most limited (joint hypomobility). Once the therapist identified what he/she perceived to be joint hypomobility when gliding the proximal humerus in a specific direction, two to three 30-s bouts of a low-velocity, oscillatory mobilization, or Maitland Grade IV–IV+ (Maitland, 1999) was applied in that direction. If this failed to result in immediate increases in PROM, high-velocity, low-amplitude (HVLA) (Maitland, 1999) manipulations were performed. To ensure the block did not wear off before completion of the intervention, it was not possible due to time constraints to record PROM measurements after the application of each mobilization/manipulation technique. However, in our four cases, the addition of these HVLA thrust techniques appeared to result in additional gains in shoulder PROM beyond those attained after the application of the two techniques previously described by Placzek et al. (1998) and Roubal et al. (1996). All manipulations performed were shortlever-arm, low-amplitude procedures. As advocated by

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Placzek et al. (1998) and Roubal et al. (1996), several measures were taken in attempt to avoid brachial plexus injury: (1) an assistant stabilized the scapula against the trunk and in an elevated position; (2) the cervical spine was positioned in ipsilateral sidebending and (3) the elbow was never fully flexed or fully extended. Following the manipulation session, PROM measurements were again recorded. Finally, with the patient resting in supine and the patient’s hand placed behind his/her head, the treated shoulder was wrapped in an ice pack for approximately 20 min. Patients were then instructed in active assisted ROM (AAROM) exercises and instructed to perform these exercises every 2 h at home, when awake, for the next 24 h. The AAROM exercises included: wand exercises for flexion, abduction, internal and external rotations. They were also instructed to apply ice packs to the shoulder for 20 min every 2 h with the ice packs circumferentially around the shoulder while lying supine, hand resting behind their head (the combined position of abduction and external rotation). Patients followed-up with the treating physical therapist daily for 1 week and received further GH joint mobilization Grade II–IV+ (Maitland, 1999), ROM exercises, and cryotherapy. Home programs included active, active assisted and passive shoulder ROM exercises. After the first week, patients were treated three times per week to address individual impairments in shoulder motion and strength, and typically discharged to a home program after 3 weeks. See Appendix A for an example of the exercise program and Appendix B for a sample clinical pathway.

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immediately after the manipulative intervention. Most initial gains in PROM and all improvement in the disability scores were maintained at the patients’ final follow-up visit. Additionally, Patients #1 and #2 had full, pain-free AROM that was equal to the opposite, non-involved shoulder and full pain-free motion with activities. Patient #3 missed several post-manipulation treatment sessions and was unable to reproduce the home exercise program. Therefore, compliance with the home program was questionable. Patient #4’s only remaining symptom was occasionally slight pain after rolling onto his affected shoulder at night. Patients #1 and #4 had follow-up video fluoroscopy studies at the 6-week follow-up visit and Patient #1 again received a video fluoroscopy study at the 12-week visit. The studies were performed in the same manner as previously described. In contrast to the baseline video fluoroscopy studies, the 6- and 12-week follow-up sessions for Patient #1 and the 6-week follow-up session for Patient #4, video fluoroscopy demonstrated a smooth, ‘‘normal’’ GH motion. Figs. 2a and b are end-range images of Patient #1’s video fluoroscopy study for the involved versus uninvolved side, respectively, prior to the initiation of the manipulative intervention. Fig. 3 shows the same patient’s involved shoulder at the 12-week follow-up evaluation and illustrates the appropriate gliding of the humeral head caudally as the patient performs active shoulder abduction.

3. Discussion 2.4. Outcomes Pre- and post-manipulation and follow-up SPADI and PROM scores at baseline, 3-week, 6-week, and 12week follow-up are reported in Fig. 1 and the Table 1, respectively. Throughout the manipulation treatment and the subsequent follow-up periods, no adverse events were reported. All patients demonstrated improvements in both PROM measurements and disability scores

Fig. 1. SPADI scores for each patient.

Although a similar treatment approach as described by Placzek et al. (1998) and Roubal et al. (1996) was utilized in this case series, several aspects of our patients’ care were unique. After using the techniques described by these authors, therapists also performed further mobilization/manipulation in the directions of remaining perceived joint hypomobility. Although not measured, the additional techniques appeared to yield immediate and substantial additional gains in shoulder ROM in every case. These gains were made in light of the study by Gokeler et al. (2003) that reported no significant changes in humeral head distances with traction force applied to the GH joint in the maximally loose pack position when compared to the closed pack position. Perhaps this is due to the specific direction and grade of the mobilization used by the authors in this study. It should be noted that Hsu et al. (2000a, b) in two separate cadaver studies reported significant increases in GH abduction immediately following anterior–posterior glides and significant increases in GH abduction immediately following caudal glides. Although outcomes for only four patients are reported, it is our opinion that the additional gains in mobility

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Table 1 PROM measurements in degrees, for patients at baseline, immediately after the manipulative intervention, and at specific follow-up sessions Patient 1

Pre-treatment Immediately post-Rx 3 weeks 6 weeks 12 weeks a

Patient 2

Patient 3

Patient 4

Flex

Abd

IR

ER

Flex

Abd

IR

ER

Flex

Abd

IR

ER

Flex

Abd

IR

ER

120 170 165 160 160

90 155 170 165 165

25 75 70 65 70

40 100 105 90 95

115 135 150 140

50 90 95 130

25 70 70 55

5 35 35 95

110 160

70 160

20 90

25 45

a

a

a

a

115 170 135 165 165

85 160 120 120 120

25 70 60 40 40

30 85 65 55 55

a

a

a

a

130 125

110 110

40 70

40 50

Denotes measurement not obtained.

Fig. 3. This figure is the same patient 12 weeks post-manipulation using the same video fluoroscopic techniques at end-range abduction. Notice the improved inferior glide of the humeral head relative to the glenoid.

Fig. 2. Video fluoroscopic image at end-range abduction in Patient #1: (a) is the uninvolved shoulder and (b) is the involved shoulder prior to manipulation. Notice the relation of the humeral head to the glenoid fossa in each figure.

attained though the utilization of our model of treatment were important enough that researchers should consider this approach in future clinical trials. Placzek et al. (1998) and Roubal et al. (1996) outlined a extensive post-manipulation protocol. These authors used many physical modalities in an attempt to decrease

pain and enhance rehabilitation. Patients were also given an extensive exercise regime to perform both in the clinic with supervision and as a home program. In contrast, our post-manipulation rehabilitation program was designed to maintain gains in shoulder mobility and specifically address each individual patient’s remaining impairments while minimizing the amount of time that the patient had to come to the facility for his/her rehabilitation. Compared to the protocols used by Placzek et al. (1998) and Roubal et al. (1996), our patients were treated with fewer exercises and the use of physical modalities (except for cryotherapy) was eliminated. Further, our patients required approximately four to five fewer post-manipulation PT visits than patients in the previous studies. In our opinion, an extensive post-manipulation rehabilitation program may not be necessary; a more parsimonious rehabilitation program may result in favorable gains in mobility and improvements in disability scores, while conserving valuable patient and clinic time and resources.

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Additionally, although many theorize about the effects that AC has on normal arthrokinematics (Maitland, 1999) and the effect of an intervention on the arthrokinematics, documented cases of patients receiving video fluoroscopy studies to demonstrate a loss of normal joint kinematics before intervention and return of more normal joint kinematics after the application of an intervention have not been found. It is believed that this is the first attempt to demonstrate this. Video fluoroscopy of anterior–posterior views during active shoulder abduction revealed increased caudal translation of the GH joint following manipulation when compared to the pre-manipulation video fluoroscopy studies. Because video fluoroscopy is a non-invasive, low-risk, and expedient imaging modality it is therefore considered that it may be an ideal tool to monitor the arthrokinematics of the GH joint. Researchers should consider including the use of video fluoroscopy in future studies when investigating the effects of interventions on the mechanics of the GH joint. Except for the regional interscalene block performed by the anesthesiologist, all interventions in this study and others (Roubal et al., 1996; Placzek et al., 1998) were performed by physical therapists. The Guide to Physical Therapist Practice (American Physical Therapy Association, 2001) defines mobilization/manipulation as ‘‘a manual therapy technique comprising a continuum of skilled passive movements to the joints and/or related soft tissues that are applied at varying speeds and amplitudes, including a small-amplitude/high-velocity therapeutic movement’’. The Guide lists mobilization/manipulation as an intervention appropriate for the care of patients with AC. Since physical therapists possess and already utilize these mobilization/manipulation skills in the care of patients with AC without anesthetic blocks, it is our belief that physical therapists are ideally suited to be the practitioner of choice to perform this treatment on patients who have received a regional interscalene block.

4. Conclusion The AC patients in this case series, treated with translational manipulation following an interscalene block, showed rapid improvement in PROM and improved levels of disability as measured by the SPADI. The results are consistent with previous reports (Roubal et al., 1996; Placzek et al., 1998) demonstrating that, in patients with AC, this type of intervention may result in positive outcomes that are considerably quicker than improvements attributed to the natural history of this disorder. It appears that translational manipulation by a physical therapist can be a safe and potentially effective

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treatment option for these patients, even those presenting with underlying rotator cuff pathology as demonstrated by MRI. It is our opinion that this intervention should be considered for patients with AC if a trial of more conventional treatment strategies has failed to produce satisfactory results. Additionally, the use of video fluoroscopy may be an ideal imaging modality for further investigation of the biomechanical changes that occur in the GH joint after the application of an intervention in patients with AC. However, before this treatment method for shoulder AC is advocated for wide spread use, randomized controlled trials comparing this treatment to competing treatments are warranted.

Appendix A. Post-anesthesia shoulder program A.1. Same day

    



Pre-anesthesia PROM measurements. Mobilizations/manipulations to address capsular restrictions. Post-anesthesia PROM measurements. Instruct in home exercise program of AAROM for shoulder flexion. To be performed every 2 h for 5 min to end range with 5 s holds. Ice pack around the shoulder for 20–30 min. Patient should be resting supine with hand behind the head to encourage continued stretch in external rotation and abduction. Use of ice at home 20–30 min following exercise.

A.2. 1–5 days post-manipulation

 



Patient to attend daily PT sessions for shoulder mobilization, exercise and ice. Instruct in AAROM wand exercises for flexion, abduction, internal and external rotation, selfstretches for horizontal flexion. Ice to the shoulder following treatment in supine with hand behind head for 20–30 min. Continue with home exercise program every 2 h for the first week. Ice 20–30 min after treatments.

A.3. Second and third weeks

     

Continue with clinic sessions three times per week. Continue with shoulder mobilizations to address tightness/restrictions. Advance to rotator cuff strengthening as motion and pain allows. Ice following treatment as needed. Continue with home program. Discharge at the end of third week to home program.

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Appendix B. Pre-manipulation pathway for frozen shoulder patients Pre-Manipulation Pathway for Frozen Shoulder Patients Physical Therapist (PT) determines that the shoulder condition is appropriate for manipulative treatment

PT counsels patient on risks/ benefits of the procedure, as well as other treatment options. Patient completes a Shoulder Pain and Disability Index (SPADI)

PT coordinates with anesthesia service for interscalene block and schedules patient’s manipulation session immediately following.

PT coordinates with referring physician for Medrol 6-day dose pack and instructs patient to take first dose one day prior to procedure.

PT orders plain radiographic films of affected shoulder. MRI may be considered to note any existing pathology (i.e. rotator cuff tear, labral defect, etc) prior to manipulation.

On the day of procedure, patient will report directly to anesthesia. The patient must arrange for their own escort to assist them from anesthesia to Physical Therapy, as well as to serve as designated driver to escort patient home following PT treatment.

PT will take PROM measurements both prior to, and following manipulation and instruct patient in post-manipulative care and exercise plan.

PT will follow patient daily for at least 1 week to ensure all manipulation gains are maintained and that the patient is compliant with entire program.

PT may reduce clinic patient visits as appropriate after one week, providing there are no complications and patient is progressing well with program.

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Nevaiser R. Painful conditions affecting the shoulder. Clinical Orthopaedics and Related Research 1983;173:63–9. Neviaser R. Adhesive capsulitis. Orthopaedic Clinics of North America 1987;18:439–43. Norkin C, White D. Measurements of joint motion: a guide to goniometry, 2nd ed. Philadelphia: F A Davis; 1999. Omari A, Bunker T. Open surgical release for frozen shoulder: surgical findings and results of the releases. Journal of Shoulder and Elbow Surgery 2001;10:353–7. Parker R, Froimson A, Winsberg D, Arsham N. Frozen shoulder, Part II: treatment by manipulation under anesthesia. Orthopedics 1989;12(7):989–90. Pearsall A, Speer K. Frozen shoulder syndrome: Diagnostic and treatment strategies in the primary care setting. Medicine and Science in Sports and Exercise 1998; S33–9. Placzek J, Roubal P, Freeman D, Kulig K, Nasser S, Pagett B. Long term effectiveness of translational manipulations for adhesive capsulitis. Clinical Orthopaedics and Related Research 1998;356:181–91. Roubal P, Dobritt D, Placzek J. Glenohumeral gliding manipulation following interscalene brachial plexus block in patients with adhesive capsulitis. Journal of Orthopaedic and Sport Physical Therapy 1996;24:66–77. Sandor R. Adhesive capsulitis: optimal treatment of ‘‘frozen shoulder’’. The Physician and Sportsmedicine 2000;28:23–9. Schwitalle M, Betz U, Eckardt A, Rompe J, Meurer A, Karbowski A. Rehabilitation success after shoulder manipulation under anaesthesia supported by continuous interscalene block. European Journal of Physical Medicine and Rehabilitation 1998;8:44–7. Shaffer B, Tibone J, Kerlan R. Frozen shoulder: a long-term followup. The Journal of Bone and Joint Surgery 1992;74-A(5):738–46. Siegel L, Cohen N, Gall E. Adhesive capsulitis: a sticky issue. American Family Physician 1999;59:1843–50. Thomas D, Williams R, Smith D. The frozen shoulder: a single blind controlled study of manipulation treatment compared with local hydrocortisone: Abstract. Australian and New Zealand Journal of Medicine & Science in Sports and Exercise 1981;11:726–7. Tukmachi E. Frozen shoulder: a comparison of western and traditional Chinese approaches and a clinical study of its acupuncture treatment. Acupuncture in Medicine 1999;17:9–21. van der Heijden G, van der Windt D, de Winter A. Physiotherapy for patients with soft tissue shoulder disorders: a systematic review of randomized clinical trials. British Medical Journal 1997;315(Jul):25–30. van der Windt D, Koes B, Deville W, Boeke A, de Jong B, Bouter L. Effectiveness of corticosteroid injections versus physiotherapy for treatment of painful stiff shoulder in primary care: randomised trial. British Medical Journal 1998;317:1292–6. Vermeulen H, Obermann W, Burger H, Kok G, Rozing P, van den Ende C. End-range mobilization techniques in adhesive capsulitis of the shoulder joint: a multiple-subject case report. Physical Therapy 2000;80:1204–13. Williams J, Holleman D, Simel D. Measuring shoulder function with the shoulder pain and disability index. Journal of Rheumatology 1995;22:727–32. Winters J, Sobel J, Groenier K, Arendzen H, Meyboom-de Jong B. Comparison of physiotherapy, manipulation, and corticosteroid injection for treating shoulder complaints in general practice: Randomised single-blind study. British Medical Journal 1997; 314:1320–5.

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Letter to editor I would like to compliment T. Flanagan et al. (8(4) 2003) on a wonderfully clear, precise, and easy to understand flow-chart for use in the professional issue section dealing with justifying the on-going physiotherapy management of long-term patients. With their permission allow me to add a few comments/ suggestions. 1. The chart is applicable to all types of patients, not only those with a long-term problems. It should be the basis of educational programs in physiotherapy school. 2. The introduction and implementation of the psychosocial model and its influence in the treatment plan is not mentioned or referred to. May I suggest that this

1356-689X/$ - see front matter r 2004 Published by Elsevier Ltd. doi:10.1016/j.math.2004.08.007

should by added in the block entitled ‘‘Use of two functional outcome measures’’. 3. It seems obvious a time framework was not mentioned or included in the chart, but I would suggest that it should be added in the beginning as a determining factor to further assist the practitioner when the realistically planning the management program.

Anthony Kaplan Jerusalem Physiotherapy Institute P. O. Box 6986 91069 Jerusalem, Israel E-mail address: [email protected]

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Letter to the Editors Response The publication of our article in an international journal reflected our belief that the professional issue raised in the article had worldwide application. It is reassuring to receive such a positive response from a person involved in physiotherapy education in Jerusalem. We welcome the opportunity to reply to Mr. Kaplan’s suggestions. 1. The authors agree that the flow chart is applicable to all patients but its development focused on the physiotherapy management of long-term patients. This focus was in response to the inherent difficulty associated with clinical justification of long-term patient management; if a patient recovers to his/her pre-injury status in a relatively short period then there is no issue. The management of the acute and sub acute patient as well as the long-term patient has been developed through an internal process at the TAC. The interested reader can access this flow chart on the TAC web site: www.tac.vic.gov.au.The aim of this more complete flow chart is consistent with the published flow chart in that the authors are interested in helping the treating physiotherapist to follow a framework that utilizes measurement as the cornerstone to clinically justify specific physiotherapy strategies or interventions. The flow chart is not intended as a total system. In this sense, the authors agree with Mr. Kaplan when he suggests, ‘‘it should be the basis of educational programs in physiotherapy school’’. 2. The authors presume Mr. Kaplan’s reference to the psychosocial model should read biopsychosocial model. Unlike Mr. Kaplan’s preference for this model to be added to the ‘‘Use of two functional Outcome Measures’’ the authors believe that the treating physiotherapist should consider physical, social and psychological aspects of a long-term patient’s condition in the ‘‘review diagnosis and management’’ section. This ‘‘review and diagnosis and management’’ as indicated in the flow chart is

triggered when serial functional outcome measures do not demonstrate significant change and the patient has not returned to his/her pre-injury status. If this scenario occurs then, as the flow chart and the text of the article suggest, the treating physiotherapist should refer the patient onto an appropriate health professional after pondering a series of issues that in part relate to the biopsychosocial model. 3. Mr. Kaplan’s reference to time frame is partly addressed in the flow chart incorporating the acute and sub-acute stages of a condition referred to in point one. The authors did not wish to be overly directive with time frames as there are too many variables with regard to pathology and management. However, with more widespread use the issue of time frames and dosage (i.e. frequency and duration) of physiotherapy intervention and measurement strategies will develop and allow a greater, but never complete, consistency in the directing of time frames for the application and interpretation of the flow chart. The flow chart presently provides a schema to assist the treating physiotherapist (and we contend all health professionals) a means to clinically justify the management of long-term patients. The future development of the flow chart will depend on the ability of the profession to adopt the key theme of measurement using validated functional measures to determine the roles of the health professional and the patient in the natural history of a condition. It is a pertinent and evolving issue for the profession and we are grateful to people like Mr. Kaplan for taking the time to enhance this process.

Tony Flanagan, PaulCoburn, MariaZylinski Transport Accident Commission Medical Panel, Fairfield Physiotherapy and Sports Injuries Centre, 181 Station Street, Fairfield 3078, Australia E-mail address: [email protected]

*

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Corresponding author.

Manual Therapy (2005) 10(2), 174

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