The Double Dynamic Martin Screw (DMS): Adjustable Implant System for Proximal and Distal Femur Fractures

K.-K. Dittel ] M. Rapp ] (Eds.)

The Double Dynamic Martin Screw (DMS) Adjustable Implant System for Proximal and Distal Femur Fractures

K.-K. Dittel M. Rapp (Eds.)

The Double Dynamic Martin Screw (DMS) Adjustable Implant System for Proximal and Distal Femur Fractures In collaboration with W. Abendschein, A. Ateschrang, S. Decker-Burgard, M.-R. Felenda, K. K. Förster, D. Janssen, B. Marquardt, W. Miller, K. M. Peters, R. Plank, S. Uppenbrink, R. Zirn

With 287 Figures in 400 separate Illustrations and 24 Tables

12

Karl-Klaus Dittel, Prof. M.D. Matthias Rapp, M.D. Clinic of Orthopaedic Surgery, Traumatology and Reconstructive Surgery Marienhospital Stuttgart – Academic Hospital of the University of Tübingen, Germany Böheimstraße 37, D-70199 Stuttgart

ISBN 978-3-7985-1841-4 Steinkopff Verlag Bibliographic information published by Die Deutsche Nationalbibliothek Die Deutsche Bibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data is available in the Internet at http://dnb.d-nb.de. This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Steinkopff Verlag. Violations are liable for prosecution under the German Copyright Law. Steinkopff Verlag a member of Springer Science+Business Media www.steinkopff.com © Steinkopff Verlag 2008 Printed in Germany The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Product liability: The publishers cannot guarantee the accuracy of any information about the application of operative techniques and medications contained in this book. In every individual case the user must check such information by consulting the relevant literature. Medical editors: Dr. med. Gertrud Volkert, Petra Elster Production: Klemens Schwind Cover design: Erich Kirchner, Heidelberg Typesetting: K+V Fotosatz GmbH, Beerfelden Printing and binding: Stürtz GmbH, Würzburg SPIN 12443000

105/7231 – 5 4 3 2 1 0 – Printed on acid-free paper

Freedom of movement: Its value will be only recognized, when it is restricted Sir J. Charnley, 1957

Foreword

The scope and importance of hip fractures is almost incomprehensible. With a world wide incidence of close to 2 million cases per year, these fractures pose a daunting challenge to our ability to affect and treat this epidemic. The incidence of these fractures is predicted to grow to 6 million in 2050 including a near term baby boom spike. Add the hospital mortality rate of up to 4% and the one mortality of from 8% to 20% and the life ending effect of these fractures becomes a glaring reality. Of those who initially survive their fracture, about 50% never walk the same again. The social problem in the care of these elderly people is enormous. Of course, any real solution to this problem will include education, prevention, surgical and hospital treatment protocols, long term rehabilitative efforts, social adjustments and a generous contribution of money. This publication is primarily directed to the amplification of a new treatment modality that addresses only a fraction of the problem. It is, however, a quantum leap in the evolution of fixation with compression hip screws which are still the gold standard for surgical stabilization of pertrochanteric hip fractures. The Dynamic Martin Screw (DMS) addresses the issue of adjustability of the fixation angle with appropriate mechanical strength characteristics that were lacking in its historical predecessors. It exhibits the unique ability to allow the surgeon to improve the reduction to a more advantageous valgus angle even after it is rigidly attached to the femur. This provides a more stable construct that will allow for a more successful recovery of the patient to their previous ambulatory life. In addition, the device is ideally suited for a new challenge in hip fractures, the MRI fracture. These are undisplaced fractures diagnosed almost entirely by magnetic resonance imaging. Since they are, by definition, undisplaced, the infinite adjustment of the femur neck angle of this device is the perfect solution. The variable angle system has been adapted for paediatric use. While useful for fracture fixation, it is an excellent option for fixation in the varus femoral osteotomy for dysplastic hips and subluxation in children with cerebral palsy. Further on the supracondylar version is very valuable for distal femur fractures. The supracondylar version with cable extraordinarily is suited for the devastating periprosthetic femoral fracture in the total hip patient. This situation, by the way, is a new epidemic! Washington D.C., Summer 2008

Walter Abendschein, M.D.

Preface

Much has been written about changes in medicine – mankind has gone through – changes which influenced the development of medical speciality decisively and surely many more changes will continue to take place in coming years. Obviously only some of the advances in the treatment of fractures and degenerative diseases of the human motor system may be regarded as milestones in the development of orthopaedic and trauma related surgery. Major advances have been made specially in the treatment of femur fractures over the last five decades. There is no doubt that one milestone in the middle of the last century can be attributed to Ernst Pohl, a genious engineer from Kiel, who developed the first sliding device for osteosynthesis of hip fractures. He opened a new area in the field of conventional hip joint reconstruction, consequently embettering and developing an implant system, enabling the patient to walk with full weight bearing at an early time, reducing complications decisively and functional deficits to a minimum. Our book deals with trauma surgery at the hip joint and it includes all kinds of fractures from the femoral neck area as well as the intertrochanteric and the subtrochanteric area. We know that there is no single method of treatment existing which could be used adequately for all type of fractures at the proximal femur. We believe on the other side that with the development of the DMS since 1993 and the experiences we have made personally with the new implant a spectrum of indications for its implantation has been opened which is broader than the spectrum of many other implants which are used for fracture fixation at the hip. This does not mean that we belong to the type of surgeons who claim that one could use a single implant for all type of fractures. It is obvious that the better option is to use the best implant for an existing problem. We have made the attempt to give a tailormade solution for treatment of joint localised fractures at the femur. Our experience over 15 years show that a great number of problems can be solved with the DMS under the special aspect of its unique adjustability and anatomical congruence. Every year publications about fractures at the proximal femur present new biomechanically embettered or descripted ideal implants. Mostly ideal fractures with ideal results are presented by expelling the results about problems, complications and implant failures. That’s why we have included in the book several chapters which are dedicated to problem cases and pathological fractures for which the surgical management is controversially discussed until our days. The book finally includes chapters about perioperative antibiotic therapy, thrombo-embolism prophylaxis, postoperative physiotherapy and osteoporosis management. We have written our book for colleagues who are working in trauma surgery and we hope that we have fulfilled the demands of objectivity. The reader should treat our attempt with leniency. Stuttgart, Summer 2008

Karl-Klaus Dittel Matthias Rapp

Dedicated to my surgical teachers

Ordinarius Prof. Dr. med. Wolfgang Schiefer Formerly Medical Director Neurosurgical University Clinic Erlangen Reproduced with kind permission from Stadtarchiv Erlangen

Prof. Dr. med. Friedrich Pampus Formerly Medical Director Neurosurgical Clinic Katharinenhospital Stuttgart Reproduced with kind permission from Pressefoto Kaufmann & Kaufmann, Stuttgart

Prof. Dr. med. Erwin Kraft Formerly Medical Director Surgical Clinic Marienhospital Stuttgart Reproduced with kind permission from Public Relations Office, Marienhospital Stuttgart

Dedicated to my surgical teachers

Ordinarius Prof. Dr. med. Dr. med. h.c. mult. Siegfried Weller Formerly Medical Director BGU and University Clinic of Traumatology Tübingen

In sincere gratitude The book is dedicated to Siegfried Weller at the occasion of his 80th birthday Karl-Klaus Dittel

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XI

Acknowledgments

In the front line we have to notice to be indebted to the authors of this book who have spent their precious time for preparing, revising, updating, writing and overworking their chapters. We are thankful for their work which they have done unselfishly. They have prepared their contributions and manuscripts reliable in a very short time and we hope that our readers will give the attentiveness to their chapters they have earned. To the companies who have supported the printing we have to express our deep thank. Without their help the production of this book would not have been possible. ] ] ] ] ] ] ]

KLS Martin Pfizer Stryker Codon Carstens Aesculap Cardinal Health

– Thanks for their support in form of a contribution to the print costs. – Thanks for the support in form of an advertisement. – Thanks for the support concerning the necessary illustrations (Mrs. Rose Baumann) which had to be drawn for the book. ] Thanks to the Steinkopff Verlag crew (Mrs. Dr. med. Gertrud Volkert, Mrs. Petra Elster, Mr. Klemens Schwind) for their important advices and comments which influenced the outcome of the book positively. ] Thanks to our secretary Mrs. Reim who showed no tiredness in writing the texts repeatedly. ] Thanks to our colleagues who have stimulated us continuously with their ideas and mental contributions to do our very best by publishing. ] Thanks to the colleagues and friends Bud Abendschein, M.D., Washington D.C. USA and Don Lyddon, M.D., Rockford USA who did a thoroughly job by translating some of the german texts into english. We are very lucky that the printing of the book was possible based on an effective and trustworthy collaboration with all involved persons who have enabled the completion in time. Karl-Klaus Dittel Matthias Rapp

Contents

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1

K.-K. Dittel

Conventional hip surgery in traumatology 1

A century of experiments and experiences . . . . . . . . . . . . . . . . . . . . . . .

7

K.-K. Dittel

Technical properties of the DMS 2

The analysis of hip compression screws made of implant steel under static and limit load requirements . . . . . . . . . . . . . . . . . . . . . . . .

15

R. Zirn ] ] ] ]

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The scope of the work Methods . . . . . . . . . . Conclusion . . . . . . . . . Reference . . . . . . . . . .

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Implants and instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

21

M. Rapp, K.-K. Dittel

Radioanatomy 4

Abnormal radiographic anatomy of the proximal femur . . . . . . . . . . . . .

29

B. Marquardt ] References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

44

XVI

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Contents

Fracture classification at the proximal femur 5

Statistical items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

47

M. Rapp ] AO-classification of trochanteric fractures . . . . . . . . . . . . . . . . . . . . . . ] AO-classification of femur neck fractures . . . . . . . . . . . . . . . . . . . . . . .

48 48

Surgical technique for fracture treatment 6

Operative procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

51

M. Rapp, K.-K. Dittel ] Surgical technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

52

Operative procedures (Case reports) 7

The prognosis of the femur neck fracture after headpreserving osteosynthesis . . . . . . . . . . . . . . . . . . . . . . . . . . .

61

A. Ateschrang ] ] ] ]

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Introduction . . . . . Method and results Discussion . . . . . . Conclusions . . . . .

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61 61 64 64

Intermediate DMS (2/3 implant) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

69

K.-K. Dittel, M. Rapp

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Stabilization of intertrochanteric fractures with the Dynamic Martin Screw (DMS) . . . . . . . . . . . . . . . . . . . . . . . . . .

71

M. Rapp ] Type of fracture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

71 72 75

10 The 31 A 3-3 fracture: an unstable problem . . . . . . . . . . . . . . . . . . . . . .

77

M. Rapp ] Type of fracture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

77 78 80

Contents

11 Subtrochanteric femur and proximal femur shaft fractures . . . . . . . . . . .

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85

M. Rapp ] Type of fracture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

85 86 87

12 Application of the Dynamic Martin Screw (DMS) in the intertrochanteric osteotomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

95

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13 Distal femur fractures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

101

M.-R. Felenda ] ] ] ] ] ]

Treatment strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . Indications for operation . . . . . . . . . . . . . . . . . . . . . . Stabilization of the distal femur fracture with the DMS Postoperative management . . . . . . . . . . . . . . . . . . . . . Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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14 Pathologic fractures and osteolyses at the femur . . . . . . . . . . . . . . . . . .

107

S. Uppenbrink, K.-K. Dittel ] The pathologic femur fracture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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15 The use of an innovative femur neck prosthesis in case of complications after hip fracture surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 K.-K. Dittel

16 Exceptional indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

117

K.-K. Dittel, M. Rapp ] Special problem cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] The future! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] Century of the aged! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Additional and adjuvant measurements and procedures 17 Systemic antibiotics in the prophylaxis and therapy of postoperative infections in patients with osteosynthesis of the femur . . . . . . . . . . . . .

129

S. Decker-Burgard ] ] ] ] ]

Causative pathogens . . . . . . . . . . . . . . . . . . . . . . . . . . Antibiotic prophylaxis . . . . . . . . . . . . . . . . . . . . . . . . Selection of antibiotics . . . . . . . . . . . . . . . . . . . . . . . . Application of antibiotics for perioperative prophylaxis References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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130 130 132 134 135

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Contents

18 Prevention of venous thromboembolism in hip surgery . . . . . . . . . . . . .

137

D. Janssen ] ] ] ]

Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual risk factors of thrombosis . . . . . . . . . . . . . . . . . . . . . . . Thromboprophylactic measures . . . . . . . . . . . . . . . . . . . . . . . . . . . Relevant side effects of subcutaneous pharmacological prophylaxis in hip surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ] Forensic aspects of thromboprophylaxis . . . . . . . . . . . . . . . . . . . . . ] References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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19 Physiotherapy after surgery for proximal femur fractures . . . . . . . . . . .

143

R. Plank ] ] ] ] ] ] ]

Pre-surgical . . . . . . . . . . . . . . . . . . . . . . . . . . . Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Prescribing physiotherapy and physical therapy Early physiotherapy . . . . . . . . . . . . . . . . . . . . Therapeutic exercises . . . . . . . . . . . . . . . . . . . Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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143 144 144 144 145 146 152

20 Operative revisional management . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

153

M. Rapp, K.-K. Dittel ] ] ] ] ] ]

Revisional Revisional Revisional Revisional Revisional Revisional

management management management management management management

case case case case case case

20.1 20.2 20.3 20.4 20.5 20.6

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21 Evidence-based drug treatment of osteoporosis . . . . . . . . . . . . . . . . . . .

161

K. K. Förster, K. M. Peters ] ] ] ] ]

Introduction . . . . . . . . . . . . . . . . . . . . . Prevention and treatment of osteoporosis Other treatments for osteoporosis . . . . . Evidence-based conclusion . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . .

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Closing remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

173

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References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

175

Subject Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

179

Authors

Abendschein, Walter, Prof. M.D. 35771 Snake Hill Road Middleburgh Virginia 20117, USA

Marquardt, Barbara, M.D. Traubergstraße 7 D-70186 Stuttgart

Ateschrang, Atesch, M.D. Clinic of Traumatology and Reconstructive Surgery Berufsgenossenschaftliche Unfallklinik Tübingen Schnarrenbergstraße 95 D-72076 Tübingen

Miller, Wolfgang, M.D. Martin-Luther-Straße 37 D-70771 Leinfelden-Echterdingen

Decker-Burgard, Sabine, M.D. Zuckschwerdtstraße 29 D-65929 Frankfurt Dittel, Karl-Klaus, Prof., M.D. Clinic of Orthopaedic Surgery, Traumatology and Reconstructive Surgery Marienhospital Stuttgart – Academic Hospital of the University of Tübingen, Germany Böheimstraße 37 D-70199 Stuttgart Felenda, Manfred-Raymund, M.D. Clinic of Orthopaedic Surgery, Traumatology and Reconstructive Surgery Marienhospital Stuttgart – Academic Hospital of the University of Tübingen, Germany Böheimstraße 37 D-70199 Stuttgart Förster, Klaus K., Ph.D. Medical Consultant Osteoarthritis/Osteoporosis Igelweg 3 D-51766 Engelskirchen Janssen, Detlev, M.D. Med-i-Scene Concept GmbH Schlesierstraße 9 D-91085 Weisendorf

Peters, Klaus Michael, Prof. M.D. Clinic for Orthopaedic Surgery and Osteology Rhein-Sieg-Klinik Höhenstraße 30 D-51588 Nümbrecht Plank, Rabea In der Schranne 13 D-70569 Stuttgart Rapp, Matthias, M.D. Clinic of Orthopaedic Surgery, Traumatology and Reconstructive Surgery Marienhospital Stuttgart – Academic Hospital of the University of Tübingen, Germany Böheimstraße 37 D-70199 Stuttgart Uppenbrink, Stefan, M.D. Elsenhansstraße 13 D-70469 Stuttgart Zirn, Rainer Materialprüfungsanstalt Universität Stuttgart (MPA Stuttgart, Otto-Graf-Institut, FMPA) Pfaffenwaldring 32 D-70569 Stuttgart

Introduction K.-K. Dittel

The history of non-locking implants in fracture treatment began in 1944. It was the year when the mother of the engineer Ernst Pohl (1876– 1962) died after having suffered a proximal femur fracture which was treated conservatively over several weeks by traction and immobilization. From this moment the instrument maker Pohl worked to construct an implant which could allow stable fracture fixation, early mobilization and the best conditions for fracture healing in a rapid time frame. He is given credit for having developed the first non-locking connection between an intramedullary force carrier (lag screw) and a lateral anchoring plate (barrel plate) (Fig. 1). The principle consists in a dynamic connection between an intramedullary femur head screw and a femur plate that allows self compression (sliding link principle). This new concept made it possible to minimize many of the previous complications such as head perforation, pseudarthrosis and secondary displacement of fracture fragments.

Fig. 2. Dr. med. h.c. Ernst Pohl and the draft of the patent of Pohl system 1951 (acc. to Prof. Havemann).

Fig. 1. Pohl sliding cylinder – plate system.

2

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K.-K. Dittel

Fig. 3. The sliding link principle, realization of an ingenious idea. First publication abroad: A New Principle in the Treatment of Trochanteric Fractures of the Femur. W. Schumpelick und P. M. Jentzen (1955) In: The Journal of Bone and Joint Surgery: Vol 37 A; 693.

His ideas led to the first patent on the 7th of December 1951 under the claim: “connecting implant for joint orientated fractures” (Fig. 2). The final acceptance of his revolutionary way to improve healing of hip fractures was difficult. It was delayed by antipathy and technical problems. The engineering and orthopaedic technique were developed and completed because of the dedication of this young craftsman. An era of especially fruitful cooperation between surgery and craftsmanship had started. The decisive influence of Pohl’s system is obvious in many of the devices used in modern traumatology. The revolutionary impact that this development would have on hip fracture treatment could not have been imagined at that time. The number of patients over a period of five decades and longer who have had a proximal femur fracture treated successfully with the sliding barrel principle is unknown. In the future, Pohl’s idea will provide for the survival of many more (Fig. 3). An optimized follow-up model was developed by the AO (1979) on the basis of Pohl’s system. While maintaining the “sliding barrel principle”, additional rotational stability is ensured by form-fit (i.e. by using a hexagonal screw instead of a round one) and flattening the barrel on two sides to provide corresponding sliding surfaces. Difficulties can be expected in patients with fractures at the coxal part of the femur when high age, osteoporosis and multimorbidity are together present. The type of fracture is considerably influenced by the grade of osteoporosis. Usually, quality and quantity are mutually ex-

cluding poles. However they must be brought to compatibility and respect the special problems of the fractures of the proximal femur in the elderly. The changing age structure of the population in Germany is leading to a disproportional increase of these fractures. According to statistical data from State and Private Health Insurance companies in Germany 150.000 persons per year who are older than 65 years suffer fractures in the hip joint area which subsequently require

Fig. 4. Angle adapted adjustment of the Dynamic Martin Screw.

Introduction

surgical treatment. Besides the form of fracture the choice of the implant may also imply relevant complications and influences the outcome and the ability of the single patient decisively. Basics for operative treatment of proximal and distal femur fractures: ] Clear surgical indication ] Short planning and preparation < 24 h ] Full weight bearing osteosynthesis ] Early mobilisation and physiotherapy In comprehensive form the book presents the usage of a meanwhile well installed implant (DMS) for osteosynthesis technique in the peritrochanteric region. The “double dynamic” stabilization (sliding tongue principle and angle adapted contoured fit) means a state of the art

]

fracture treatment procedure. It is a convincing alternative to achieve a biological osteosynthesis at the femur. The system includes an infinitely adjustable, flexible angle, dynamic plate with a tubular distal part. The dynamic hip plate enables an intraoperative valgus correction of the head neck fragment by the worm gear mechanism before the compression of pertrochanteric surfaces of the fracture is achieved without a removal of the implant. Because the DMS system includes the ability to be adapted to any desired angle it is not only an individual implant but also a universal implant for use at the proximal femur as well for the stabilization of fractures in the distal part of the femur. By the angle adapted adjustment complications can be reduced because tension forces are transmitted to pressure forces in the fracture area (Fig. 4).

3

Conventional hip surgery in traumatology

1 A century of experiments and experiences K.-K. Dittel

In the last 2000 years, life expectancy has increased from 25 years to about 80 years. The changing worldwide age demographics have led to an inordinate increase of proximal femur fractures (in addition to other fractures). Approximately 150.000 inhabitants of Germany over 65 years of age suffer from fractures at the hip joint requiring acute surgery every year. Besides the difficulties involved in treating such fractures adequately as well as the increase in the number of cases we are now seeing makes it a tremendous challenge to provide the highest quality of surgical care. Frequent concomitant and complicating conditions in hip fracture patients include advanced age, pronounced osteoporosis and multiple morbidity. Fracture type and subsequent selection of stabilization meth-

a

b

Fig. 1.1 a–c. Historical fracture scenario: consolidated proximal femur fracture.

od and implant are only some of the factors that relate to outcomes and complications. In addition to technical considerations, there is enormous economic impact and a requirement for coordination of peri-operative and post-operative care given in order to improve the rate of successful results (Fig. 1.1). An overview will be given about the development of operative treatment of fractures at the proximal femur during the last century. It is, however, not intended to focus every facet of the great variety of implants or therapeutic modalities. During the first period, which lasted from the beginning of the last century well into the 1940’s, treatment was limited to conservative, non-surgical care with or without traction and

c

a Alemanni sepulchre anno Domini 800. b 908 varus position; c 508 internal rotation and 6 cm leg shortening.

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K.-K. Dittel

reduction. The well-known representatives of this period among others were Boehler, Goetze, Sauerbruch and Watson-Jones. The results in the period of conservative treatment of hip fractures led to the depressing experience that 75% of the patients died most commonly of fatal pulmonary embolism due to prolonged immobilization. It is not necessarily germane to discuss the causes of proximal femur fractures at this point but it should be mentioned that by well-known experience 30% result from senile osteoporosis leading to a micro-fracture that occurs before the patient falls down displacing the fracture. Pathological fractures caused by primary or secondary bone tumours are another increasingly apparent cause. A quantum leap in the treatment of proximal fractures of the femur took place when the use of a nail was introduced as a method of fracture fixation in 1931 by M. Smith Peterson. He published additional results on femur neck and intertrochanteric fracture treatment using a “triple lamellar pin” also named “tri-flanged-nail” which was shaped like a star in cross section. It was indeed the beginning of a new revolutionary era in fracture treatment. Not only the mortality rate could be cut down from 75% to 25% but also the fracture-healing rate could be reversed from the previous 25% to 75%. This was a decisive improvement of the results enabling the surgeon to offer his patients a method with acceptable operative results and improved prognosis for survival and the return to a reasonable quality of life. It has to be considered the first revolution in conventional surgery of the hip joint. After the successful introduction of the “triple lamellar pin” in the treatment of femur neck fractures, SmithPeterson subsequently expanded its application to pertrochanteric fractures. This finally ended the use of archaic materials such as wooden and ivory pegs to fix these fractures (Fig. 1.2). The second period lasted from the forties to the sixties and seventies using a variety of rigid implants. In the course of these decades, a variety of different implants had been developed, implanted and described for stabilization of fractures at the proximal femur. Most of them are no longer in use today. Using the lamellar pin as a starting point, Jewett’s team developed an implant by combining the pin with a plate that was attached to the lateral femoral cortex by means of screws. The implants designed by Thornton (1937), Jewett (1941) and McLaughlin

Fig. 1.2. Unstable fracture. An acute life threatening situation. Approximately 150,000 proximal femor fractures per year in Germany with a population of 84 millions people ] Intertrochanteric and supracondylar area ] Unstable situation ] Irregular form ] Immobilising disability

(1947) represent parallel developments. All these implants had a rigid connection between a pin fixed in the femur neck and a plate attached to the lateral side of the femur. However, there were a large number of complications especially in unstable fractures treated with these devices. Complication rates of up to 50% were reported. Other stabilization concepts as the intramedullary elastic round nails developed by Ender (1950) and Simon-Weidner (1956) also failed to produce satisfactory results. For over 20 years the stabilization with fixed nail-plate devices was standard and unstable pertrochanteric and subtrochanteric fractures continued to carry a high complication rate. Mostly leg length discrepancy and external rotation were the nontolerable complications often leading to a secondary supracondylar fracture or an additional damage of the ipsilateral knee joint. It is clear that procedures with such a high complication rate were not the final answer. The next decisive step in conventional hip surgery was the invention of the sliding device system based on the design of E. Pohl. It represents the second revolution, incorporating his idea by using the sliding link principle in order to minimize complications and to guarantee an early fracture healing by self-compression. The development phase of this new implant occurred between 1945 and 1950 (Fig. 1.3).

1 A century of experiments and experiences

a

]

b

Fig. 1.3 a, b. The beginning in the 50-ties. AO-classification: 31 A 1.3. a p. op.; b p. w. b.

The primary importance of this development was an implant consisting of a dynamic connection between an intramedullary load bearing element in the head/neck fragment (the lag screw) and an extramedullary element, the femur side plate. This construction made it possible to achieve dynamic self-compression when weight was put on the extremity. With the clinical application of the important invention of an auto compressive sliding implant a majority of the dreaded complications inherent in the use of rigid implants could be avoided. The basic concept of the implants lies in the fact that the permanent sliding principle in operation between the lag screw in the femur head and neck and the femur plate ensures the constant contact between the fracture fragments. All subsequent implants using the sliding mechanism were based on Pohl’s concept. After the introduction of the device the complication rate could be reduced to an average of between 10 and 15%. A parallel development was the connection between a screw fixed in the femur neck and the rigid plate fixed laterally to the femur. The angle plate of Müller and Schneider (1957) was another implant with a rigid connection and used with a cancellous lag screw known as the “AO-nail” (Fig. 1.4).

Fig. 1.4. 1st–2nd–3rd generation: Pohl – DHS – DMS

The third period ranges from the fifties to 2000 improving the operative procedures by different sliding devices and the ability to implant an angle-adaptive device. Representative companies of today are Biomet, Howmedica, Martin, Richards, Stryker, Synthes and Zimmer. In 1979 the co-operative for the study of fracture fixation and healing (Arbeitsgemeinschaft für Osteosynthesefragen AO) adapted Pohl’s sliding barrel plate principle in developing a follow up model. Milling the side of the screw which had been round until that time – and machining

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corresponding surfaces in the sliding cylinder improved its postoperative rotational stability. The modification of corresponding sliding surfaces represented a major improvement in the ability to reduce or eliminate postoperative displacement. In contrast to rigid implant, fracture healing can progress in accordance with the socalled “load bearing process”. This process, which involves the use of auto compressive sliding implants, can best be defined as “load sharing”. It is a fact that the complication rate for dynamic compression plates is five times lower than that of rigid plates. Complication rates between 4 and 11% to sliding screw systems and between 21 to 53% when rigid implants are described. Sliding devices with a fixed barrel/plate angle often do not provide an ideal fit with the lateral femur cortex. The rationale for developing a new implant for fixation and stabilization of proximal femur fractures is based on a number of complications occurring with the available implants and the initial positive clinical experience with the variable angle system. Using the Pohl-System as a starting point and maintaining the barrel plate principle, a new infinitely variable dynamic plate whose angle can be adjusted was developed to stabilize all fractures in the proximal femur region. The most common technical errors that lead to complications, especially in cases of severe osteoporosis, are failure to achieve stable reduction and less than ideal positioning of the lag screw. Both of these errors can lead to varus displacement, lag screw cut out and penetration as well as non-union of the fracture. The development of an implant, which guarantees congruence between the plate and the femur shaft, helps avoid complications such as secondary subtrochanteric fracture during reduction of osteoporotic fracture fragments and the displacement of the lag screw (cutting out through the femur neck or penetrating the head). A very important characteristic and advantage of the adjustable hip system is in the infinitely variable neck/shaft angle. This enables the surgeon to exactly and anatomically apply the side plate to the femur. Most importantly, however, it allows for improvement of the valgus alignment and reduction of the fracture even after the plate has been fixed by cortical screws to the femur shaft. This enables the surgeon to reduce and fix a proximal femur fracture in the most stable and biomechanical ideal position possible. This also allows the earliest possible mobilization of

Fig. 1.5. Extra- and intramedullary osteosynthesis in 31 A 2fractures (bilateral stabilisation).

the patient. Although the variable angle system adjusts infinitely between 90 and 155 degrees, it must be remembered that the lag screw in any dynamic hip fixation system will only slide and allow compression at angles of 130 degrees and higher! The system guarantees a double dynamic stabilization by the sliding link principle and the angle adapted plate. Hopefully, this can be regarded as the third revolution. Clinical advantages of the Dynamic Martin Screw (DMS) (inaugurated in 1993) include simplification of procedure and reduced operative time in addition to the ability to improve the reduction and compression after fracture fixation is complete. The adjustable hip plate is the only truly innovative implant for hip fracture surgery in the last two decades. Considering the usual learning curve involved in any new procedure, the complication rate of these devastating fractures can be greatly reduced. A true reduction in overall morbidity and mortality, however, requires proper coordination of personnel and facilities in all phases of treatment and rehabilitation after hip fracture (Figs. 1.5–1.7; algorithms with Figs. 1.8 a, b, 1.9 a, b).

1 A century of experiments and experiences

]

Today’s global used systems in Germany ] Different dynamic hip screw systems ? 75% (n = 20) ] Different proximal femur nail systems ? 25% (n = 10)

Extramedullary implant ] Advantages – Excellent primarily reduction – Bone saving procedure – Easy bone grafting – Best sliding condition ] Disadvantages – Uncortical stress shielding – Extended soft tissue trauma – Enlarged bending forces – Osteoporotic situation

a

b

Fig. 1.6 a, b. Comparison of implant systems. Which is the better implant? What is optimal and preferable? a Extramedullary; b intramedullary

Intramedullary implant ] Advantages – Bicortical stress shielding – Reduced soft tissue trauma – Advanced stable situation ] Disadvantages – Intraoperative secondary fractures – Difficult fracture reduction – Enlarged damage of spongy bone

a

b

Fig. 1.7. Complication rate in comparison (15%).

The good and the ugly overall results are the same!

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K.-K. Dittel: 1 A century of experiments and experiences

] Algorithm for the operative treatment of proximal femur fractures (depending on fracture location, fracture type and additional findings)

Femur neck fractures Impacted type – not dislocated – primary prophylactic osteosynthesis for early functional therapy Not impacted type – dislocated (old patient, co-morbidity, bedridden, severely osteoporosis) ] not associated with coxarthrosis – indication for an extramedullary implant ] associated with coxarthrosis (fracture not sufficient for reposition, diminished bone quality) – indication for an endoprosthesis

a

b

Fig. 1.8 a, b. Femur neck fracture AO 31 B 2

Pertrochanteric femur fractures Stable situation – not dislocated or fair dislocated fracture ] not associated with coxarthrosis – indication for an intra- or extramedullary implant ] associated with coxarthrosis – indication for an endoprosthesis Unstable situation – severely or extremely dislocated fracture ] not associated with coxarthrosis (good or fair bone quality, good reduction) – indication for an extra- or intramedullary implant ] associated with coxarthrosis (heavily reduced bone quality, not sufficiently reducible situation, bedridden) – indication for an endoprosthesis

a

b

Fig. 1.9 a, b. Pertrochanteric femur fracture AO 31 A 3

Technical properties of the DMS

2 The analysis of hip compression screws made of implant steel under static and limit load requirements R. Zirn

The scope of the work The load capacity of rigid and adjustable built hip compression screws (HCS) made of implant steel X2 CrNiMo 18 15 3 (DIN 17443) were laboratory tested at room temperature and randomly examined. The HCS were also put through experiments with cyclic limit bending loads until failure. HCS implanted for the stabilization of a femoral fracture load requirement. The load level was determined by the transverse load F2 resulting from the hip load R as shown in Figure 2.1.

Methods Four rigid and adjustable hip compressions screws (HCS) are the test subjects. The rigid model with a nominal cross section of 19.1 ´ 6

Fig. 2.1. Physiological load of the hip joint.

mm has an angle of 135 8 (oscillation test) and 139 8 (static test, constant stress). The adjustable HCS (nominal shaft cross section 19.5 ´ 8.4 mm2) could be adjusted optionally in the region from about 85 8 to 135 8. The characteristic values of the implant steel material are determined by DIN 17443 and lie by Rp = 690 MPa for the elastic limit yield point and by Rm = 860–1110 MPa for the tensile strength.

] Test procedure The tests were performed on a servo hydraulic universal testing machine with a load of 7 kN. The load applied on the hip compression screw (HCS) was determined by using a load cell attached to a test cylinder. To determine the deflection of the HCS the cross head displacement of the test cylinder was used (stroke 20 mm). The parts to be tested were clamped on an adjustable angle bracket so that the transfer of force could be directed over the required angles. The test load was transmitted via a spherical cap (calotte). The distance between the break point and the axis of rotation of the angle between the shaft and the pipe was in each case 65 mm (Fig. 2.2 a, b). The HCS was tested taking into account the most frequent applications in two different installed situations at room temperature: Application under all available usages of the bolted joints (short settings free overlap 20 mm). Application without the above fixing possibility (long position, free overlap 40 mm) (Fig. 2.2 a, b). The static load tests were carried out within the chosen load levels. For the documentation of the yield characteristics especially those of the plastic strain, the HCS were completely un-

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R. Zirn

a

b

Fig. 2.2. a Long setting, b short setting. Table 2.1. Static test results Trial Design designation

1 2

Shaft cross Setting 1 Angle section (nominal) mm ´ mm

Deflection at F2 = 588.6 N F2 = 784.8 N = 80 kg 2 = 60 kg 2 (mm) (mm)

Maximum load Fmax N

Maximum load Fmax = kg 2

1299.8

132.5

Gl 8

adjustable

19.48 ´ 8.35

long

1208

3.5

4.6

9.8

A1

rigid

19.1 ´ 6.0

long

1398

4.8

9.5

18.4

833.9

85.0

A2

rigid

19.1 ´ 6.0

short

1398

2.45

3.35

18.5

1196.8

122.0

Free overlap: short = 20 mm, long = 40 mm The load force G is the product of the mass m of a body and of the (local) gravitational acceleration g. G = m ´ g with g = 9.81 m/s2 and 1 N = 1 kg m/s2 (DIN 1305 respectively DIN 1301)

loaded several times at different load levels. The tests were discontinued when a clear load drop or a very large deformation rate of the HCS appeared (deflection of 16 to 20 mm) and no appreciable load increase was noticeable. The cyclic test of the deflection limit load was controlled by sine wave loads with a test frequency 5 Hz to failure in the HCS. The maximum loads were experienced by a load ratio of upper load to lower load R = Fo/Fu = 0.01 between 600 N and 800 N (61.16 and 81.55 kg)1. The HCS were clamped at an angle of 135 8 (using the bolted fasteners with free overlap 20 mm according to Figure 2.2 a, b).

1

Fmax (mm)

In all that now follows there will be additional to the test load F (N) the corresponding weight (kg). Thus there will be given a more recognizable comparison to the weight of a person.

] Test results The test results of the static tested HCS are given in Table 2.1. In addition to the dimensions of the parts to be tested and the geometric test conditions are the measured deflection data from loads of 588.6 N (= 60 kg) and 794.4 N (= 80 kg) and at the indicated maximum load Fmax. The resulting yield curves are shown in Figures 2.3–2.5. The test results are compared with previous analysis from [1] known for the development of a Dynamic Hip Screw-plate (DHS equals are rigid HCS) with long position. The rigid HCS varies considerably from the recorded procedure of the DHS-plate and reaches a maximum load of just 833.9 N (=85 kg) (Fig. 2.3), when compared to a comparable test configuration (long setting) with greater deflection. The shorter, more rigid setting (overlap 20 mm) in Figure 2.4 compared to the long

2 The analysis of hip compression screws made of implant steel under static and limit load requirements

]

Fig. 2.3. Rigid hip compression screw (1398).

Fig. 2.4. Rigid hip compression screw (1398).

clamped HCS leads to a maximum load of 1196.8 N (= 122 kg). The rigid HCS deformed essentially in the area of the bracket. Until the test was discontinued no fractures occurred when there was a deflection of 20 mm. The statically tested, adjustable HCS with the long setting with a maximum load of 1224 N (= 135 kg) and an accompanying deflection of approximately 9 mm clearly surpassed the DHSplate performance (Fig. 2.5).

The shaft which was more inflexible (cross section 13.45 ´ 8.43 mm2) had no noticeable plastic deformation. On this HCS model the plastic deformations were concentrated at the adjustable connection elements (worm gear, worm-wheel, fork-bolt connection) between the shaft and the case. Also on the adjustable HCS there was no fracture at the applied maximum deflection of about 14 mm. After reaching the maximum load the connection worm-gear and wormwheel could not transfer the power and slipped through.

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R. Zirn

Fig. 2.5. Adjustable hip compression screw (1208).

Table 2.2. Oscillation tests

1

Trial designation

Design

Shaft cross section (nominal) mm ´ mm

Brink load F0 N

Brink load F0 = kg 1

Gl 11

adjustable

19.18 ´ 6.70

800

Gl 21

adjustable

19.13 ´ 6.72

700

Gl 10

adjustable

19.30 ´ 7.65

600

Arbitrary oscillation numbers

Failure range

81.55

64 000

Adjustable area

71.36

214 000

Adjustable area

61.16

326 000

Adjustable area

A4

rigid

18.95 ´ 6.10

800

81.55

89 300

Fastening area

A3

rigid

19.11 ´ 6.10

600

61.16

2 082 000

Fastening area

The load force G is the product of the mass m of a body and of the (local) gravitational acceleration g. G = m ´ g with g = 9.81 m/s2 and 1 N = 1 kg m/s2 (DIN 1305 respectively DIN 1301)

Table 2.2 indicates the critical load data and failure range which were established with cyclic tests of the HCS. With the adjustable HCS the incipient crack occurred at the critical limit load of 600 to 800 N between 64 000 and 326 000 cycles. In Figure 2.6 the measured critical load dependent on the applied limit loads are graphically illustrated in a double logarithmic scale. The results of the two tested HCS models (rigid and adjustable) thereby show only small variations. From the literature with the exception of the 600 N tested rigid HCS all values lie within

the given scattered band of the DHS-plate (open triangle) [1]. With the results of the literature it has to be mentioned that the crank mechanism used during lab testing can provide the real stress ratio of an implanted DHS-plate. However, at high loads this is only approximate. This leads to somewhat higher cycles because of suppressed yield effects. On the rigid model the crack always occurred in the shaft directly at the fixing point. The adjustable HCS by comparison always showed the crack in the area of the adjustable connection element.

2 The analysis of hip compression screws made of implant steel under static and limit load requirements

]

Fig. 2.6. Adjustable hip compression screw (1358).

Conclusion On rigid and adjustable HCS from implant steel X2 CrNiMo 18 15 3 lab tests were made at room temperature under static and cyclic bending loads for different clamping situations. As stress value the shearing force component of the resulting load on the hip head was used. Under static load the adjustable HCS out-performed the known performance from the literature of the DHS-plate [1]. The rigid HCS model depending on the conditions clearly had inferior performance.

The results of the cyclic tests carried out under the same conditions for both settings are within the range of those results known in the literature for the DHS-plate.

Reference 1. Regazzoni P, Rüedi T, Winquist R (1985) The dynamic hip screw-implant system: laboratory tests with the DHS. Springer, Berlin Heidelberg New York

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3 Implants and instruments M. Rapp, K.-K. Dittel

Fig. 3.1. Implants for Dynamic Martin Screw (DMS).

Fig. 3.2. DMS plates ] angle adjustment 95–1108 ] 24 mm and 34 mm tube length.

Fig. 3.3. DMS plates ] angle adjustment 95–1558 ] 24 and 34 mm tube length.

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Technical demands for extramedullary implants ] Sliding functionality ] Rotatory stability ] Congruent adjustability Fig. 3.4. DMS lag screws ] Length: 50 – 60 – 70 mm ] 80 – 90 – 100 – 110 mm

Fig. 3.5. Technical demands for extramedullary implants.

Fig. 3.6. Worm gear – pinion tongue mechanism.

Valgisation

Turning left

Turning right

Varisation

Fig. 3.7. Worm gear – pinion tongue mechanism.

3 Implants and instruments

Fig. 3.8. Dynamic Martin Screw (DMS).

1318 . . . 1378 . . . 1438 – 1498: No problem

Construction details ] ] ] ] Fig. 3.9. Construction details.

Fig. 3.10. Old dogs – new tricks.

Fig. 3.11. 50 years of successful implantation of dynamic sliding implants: 1952 Pohl, 2002 DMS.

Length of sliding cylinder 35/45 mm Integrated plate angle 128 Plate diameter 18 mm Plate thickness 6 mm

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Main characteristics ] ] ] ]

Infinitely variable neck/shaft angle Subsequent intraoperative axis correction Individual patient specific shaft congruence Applicable to proximal and distal femur fractures ] Double-dynamic stabilization – sliding link principle – angle-adapted contoured fit

Fig. 3.12. Main characteristics of the Dynamic Martin Screw (DMS)

] Advantages of Dynamic Martin Screw (DMS) ] Simplification of procedure and reduced operative time ] Infinitely adjustable to any neck/shaft angle ] Ability to achieve and improve valgus reduction and compression after fracture fixation is complete Fig. 3.13. Advantages of Dynamic Martin Screw (DMS).

] Implant congruence by anatomical adjustment to reduce two major complications ] Secondary intraoperative fracture (during reposition of osteoporotic bone) ] Dislocation of the supporting screw (cutting out of the head-neck fragment) Fig. 3.14. Implant congruence by anatomical adjustment.

3 Implants and instruments

Sliding tongue systems with rigid angle settings do not always guarantee an angle adapted precision fit !

Ideal anatomical cortical congruency

Fig. 3.15. Problems of sliding tongue systems.

Fig. 3.16. Principle of the worm gear mechanism.

]

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M. Rapp, K.-K. Dittel: 3 Implants and instruments

Fig. 3.17. Production drawing Dynamic Martin Screw (DMS), complete.

Fig. 3.18. Production drawing Dynamic Martin Screw (DMS), standard plate.

Fig. 3.19. Production drawing Dynamic Martin Screw (DMS), supporting screw.

Fig. 3.20. Production drawing Dynamic Martin Screw (DMS), compression screw.

Radioanatomy

4 Abnormal radiographic anatomy of the proximal femur B. Marquardt

Fractures of the proximal femur are typically injuries of later life. Because of their greater risk of osteoporosis women are much more frequently affected than men [1]. They are often due to negligible trauma, a fall on the hip combined with torsion. Depending on the direction of the force different subcapital fractures may occur among the three trabecular groups of the head and neck (Fig. 4.1). Figure 4.2 shows types of fractures of the proximal femur according to Haeuser [2]. Another classification of subcapital fractures by Garden that is still widely used is based on the displacement of the femoral head before reduction: 1) Incomplete fracture, with abduction or compression 2) Complete fracture, without displacement 3) Complete fracture, with partial displacement 4) Complete fracture, with total displacement. Figure 4.3 shows the groups of trabeculae in the hip joint region. Three groups can be identified in the proximal femoral portion. The trabeculae that are primarily under tensile stress curve medially below the greater trochanter to the fem-

Fig. 4.1. MRT: T-1 weighted pelvic survey (a) and magnified view of the normal right hip joint, T-1 weighted (b).

a

oral head, sparing the fovea capitis. The medial, main trabeculae are under stress from pressure, and form a second, triangular group which extends from the cortex at the level of the lesser trochanter to the femoral head. They represent a continuation of the acetabular trabeculae. The secondary, lateral stress trabeculae stretch peritrochanterically from the calcar femorale and the lesser trochanter to the greater trochanter, by-passing Ward’s triangle [8]. The widely used classification of fracture of the medial femoral neck by Pauwels is based on the angle between the fracture line and the horizontal, and differentiates between Pauwels I, II and III fractures (Fig. 4.4). Figure 4.5 shows a fracture of the medial femoral neck of the Pauwels I type pre- and post-operatively. Figure 4.6 shows a medial femoral neck fracture of the Pauwels II type (angle less than 70 degrees). Figure 4.7 shows a Pauwels III fracture. The angle between horizontal and fracture line is more than 70 degrees. All three fracture types are extra-articular in nature [12]. The partially articular as well as the completely intraarticular fractures with luxation of the femoral head (Pipkin type I to type IV) are fractures which require great force and are

b

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B. Marquardt

Fig. 4.2. Fractures of the proximal femur (Haeuser Classification). 1 medial femur neck fracture; 2 lateral femur neck fracture; 3 pertrochanteric femur fracture; 4 reversed pertrochanteric femur fracture; 5 subtrochanteric femur fracture

a

b

Fig. 4.3. Trabecular groups of the proximal femur (after Greenspan).

c

Fig. 4.4 a–c. Pauwels Classification of fractures of the medial femoral neck: a Pauwels I, b Pauwels II, c Pauwels III.

4 Abnormal radiographic anatomy of the proximal femur

a

]

b

Fig. 4.5 a, b. Axial view of the right hip joint with fresh fracture of the femoral neck, type Pauwels I (a), and pelvic survey film of the same patient, after prior internal fixation of the opposite side, stabilized with Dynamic Hip and Lag Screw (b).

a

b

Fig. 4.6 a, b. Medial femoral neck fracture, type Pauwels II, axial view of the right hip joint (a), and survey film of the pelvis (b).

therefore seen more in younger and middleaged patients. Because of the severe trauma they are often associated with fractures of the lower extremity on the same side, and also with thoracic and with skull and cerebral trauma [13, 14]. As a late sequel, due to the blood supply of the cortical rim of the femoral head through the artery in the lig. teres, a worrisome post-traumatic necrosis of the femoral head may develop [4, 9, 16].

Figure 4.8 shows a three-dimensional CT reconstruction of a fracture of the medial femoral neck. Figure 4.9 shows the less frequent fracture of the lateral femoral neck causing superior displacement of the trochanter, before and after reduction with internal fixation. This type of fracture is seen predominantly in young people. Due to the arterial vascular supply it has less of a tendency to develop a post-traumatic necrosis than the fractures of the medial femoral neck.

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B. Marquardt

Fig. 4.7. Medial femoral neck fracture, type Pauwels III.

Fig. 4.8. Lateral femoral neck fracture, axial view of the right hip joint with caudal tilt of the femoral head and superior displacement of the trochanter.

The pertrochanteric and the rare “reversed” pertrochanteric fractures are also fractures that involve the proximal femur. The fracture line of the so-called “reversed” pertrochanteric fracture crosses obliquely from the lesser trochanter through the shaft to the cortex on the opposite side. The usual pertrochanteric fracture originates generally in the lesser trochanteric region and runs obliquely cranial to the greater trochanter [5]. The lateral cortex is intact, the medial cortex shows a simple fracture (Fig. 4.10). Figure 4.11 shows another adduction fracture, with compression, and with avulsion of the lesser trochanter. Other fractures of the trochanteric region, pertrochanteric and comminuted, have one or more intermediate fragments, and run distally below the lesser trochanter (Fig. 4.12). A displaced, pertrochanteric, comminuted femoral fracture with avulsion of the lesser trochanter is shown in 3D-reconstruction in Figure 4.13. The various different projections, ventral, dorsal, and especially the rotation views, demonstrate the true extent of fracture comminution and displacement too much greater advantage than conventional radiographic views would.

4 Abnormal radiographic anatomy of the proximal femur

a

c

Fig. 4.9 a–d. Three-dimensional CT of a dislocated subcapital fracture of the medial femoral neck, not impacted, in 608 internal rotation (a), a.p. (b), and in 308 external rotation and 308

]

b

d

caudo-cranial tilt (c); axial CT section through the femoral neck (d).

33

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B. Marquardt

a

d

b

c

Fig. 4.10 a–d. Pertrochanteric femoral fracture, survey film of the pelvis (a), axial (b) and 308 caudo-cranial view (c) of

the right hip joint, and after internal fixation with dynamic hip plate (d).

4 Abnormal radiographic anatomy of the proximal femur

a

b

Fig. 4.11 a, b. Pertrochanteric femoral fracture with avulsion of the lesser trochanter, multiple breaks in the medial corti-

a

]

cal margin and small, avulsed dorsal chip fragment. Intact lateral cortex (b).

b

Fig. 4.12 a, b. Comminuted pertrochanteric fracture of the right femoral neck with several interposed fragments, which

extends distally to below the avulsed lesser trochanter. Axial view of the hip joint (a), survey view of the pelvis (b).

35

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B. Marquardt

a

b

c

d

Fig. 4.13 a–d. 3D reconstruction of a dislocated, comminuted pertrochanteric femoral fracture with avulsion of the lesser trochanter. Anterior view (a), dorsal view (b), anterior view,

a

308 caudo-cranial rotation (c), and dorsal view, 608 craniocaudal rotation (d).

b

Fig. 4.14 a, b. Pertrochanteric femoral fracture with comminution of the medial cortex and intact lateral cortex, dorso-

cranial avulsion of an additional fragment. Axial view of the left hip joint (a), survey view of the pelvis (b).

4 Abnormal radiographic anatomy of the proximal femur

a

b

c

d

]

Fig. 4.15 a–d. 3D-CT reconstruction of a fracture with destroyed lateral and medial cortex, a.p. view (a), 158 internal rotation (b), 608 internal rotation and 158 caudo-cranial an-

gulation (c). Same position in Inner-view mode (d) with excellent visualization of the comminution and dislocation.

Figure 4.14, finally, shows a fracture with multiple medial cortical breaks and an intact lateral cortex. An additional fragment is seen in dorso-cranial location. Intertrochanteric fractures can be simple, oblique-simple, transverse or comminute. An example of a 3D-CT reconstruction of a comminute fracture is presented in Figure 4.15 which shows destruction of the lateral and medial cortex. A conventional X-ray in Figure 4.16 shows a

so-called “reversed” pertrochanteric femoral fracture with breaks in the lateral and medial cortex, and an additional lateral chip fragment. Figure 4.17 shows a severely comminuted and displaced fracture. Other classifications of pertrochanteric fractures of the femur simply list two-piece, threepiece, four-piece and multi-fragmented fractures, or the division by Boyd-Griffin, into type I to IV. Also in use is the division by Evans into

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Fig. 4.16. “Reversed” pertrochanteric femoral fracture with fractured lateral and medial cortex, and additional avulsion of a small fragment in the region of and lateral to the lesser trochanter.

a

b

Fig. 4.17. Severely dislocated and comminuted pertrochanteric femoral fracture, with superior trochanteric displacement and avulsion of the greater and lesser trochanter.

c

Fig. 4.18. Subtrochanteric femoral fracture, a.p. and axial view of the hip joint (a, b) and after internal fixation with Dynamic Martin Screw (c).

4 Abnormal radiographic anatomy of the proximal femur

a

b

c

d

]

Fig. 4.19 a–d. Axial CT of a subtrochanteric femoral fracture with intact hip joint (a), and visualization of the avulsed lesser trochanter and of the dislocated subtrochanteric fracture line,

coronal reconstruction in multiplanar mode (b). Axial sections of the subtrochanteric fracture and several avulsed fragments (c, d).

undisplaced fractures; displacement of the inner cortex of both fragments, reduction possible; displacement in the region of the calcar femorale, not reducible; and finally comminution of the calcar femorale. About 40 to 45% of fractures of the proximal femur represent pertrochanteric fractures [1, 7, 8]. But because of the good blood supply of the spongy pertrochanteric fractures seldom develop the feared post-op complications of pseudarthrosis or necrosis of the femoral head, in contrast to the fractures of the medial femoral neck. These fractures are frequently associated, however, with more complex injuries, including extensive soft tissue damage. The subtrochanteric femoral fractures involve again younger patients, and a high percentage suffers from multiple traumas. Combined skull and cerebral, thoracic and pelvic injuries are frequent [3, 6, 10, 11, 16]. The fracture line runs from the greater trochanter and 5 cm distal to it. The lesser trochanter may be displaced. Besides oblique and transverse fractures there may

be torsion and comminuted fractures with multiple fragments (Figs. 4.18–4.20). Also to be mentioned among the pathological radiographic pictures of the proximal femur are metastases of the femoral head and neck [15]. Figure 4.21 a shows a survey film of the pelvis with osteolytic metastases of a plasmocytoma in the iliac wings, both femoral necks, and especially in the left subtrochanteric region. Postoperative follow-up after internal fixation with dynamic martin screw is shown in Figure 4.21 b. Another mixed metastatic process is seen in Figure 4.22 in a patient with carcinoma of the breast. The massive mixed metastatic involvement with a predominantly lytic component presents a static hazard. The diffuse metastatic spread is seen in the total body bone scan in anterior and posterior projection. Figure 4.23 shows diffuse metastatic disease of the proximal femur, including the acetabulum and the ischial bone, in a patient with prostatic cancer. This case, too, will present a static risk during the further course of the disease.

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a

b

c

d

Fig. 4.20 a–c. 3D-CT of a dislocated subtrochanteric spiral fracture with angulated wedge fragment and avulsed lesser trochanter. Anterior view, 158 caudo-cranial angulation (a), dorsal view (b), anterior view with 608 external rotation and

a

Fig. 4.21 a, b. Survey view of the pelvis with predominantly osteolytic metastases of a plasmacytoma involving both iliac wings, and the right subtrochanteric region. On the left

excellent visualization of the dislocation by more than shaft’s width (c), and view with 608 caudo-cranial angulation and 608 external rotation.

b

there is subtrochanteric osteolysis that is at particular static risk (a), and status after internal fixation with dynamic hip screw (b).

4 Abnormal radiographic anatomy of the proximal femur

a

Fig. 4.22 a, b. Right hip joint, a.p. view, with mixed metastatic disease of the trochanteric region and if the ischial bone and acetabulum in a patient with carcinoma of the

]

b

breast (a), and total body bone scan of the same patient in anterior and posterior projections (b).

Fig. 4.23. Survey view of the pelvis with diffuse metastatic disease in carcinoma of the prostate.

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For completeness sake inflammatory changes of the proximal femur should be included, due to post-operative inflammatory complications (Fig. 4.24), and changes of the femoral head due to degenerative osteoarthritis of the hip joint. In these latter cases the radiographic findings frequently do not correlate with the clinical symptoms. Chief radiological signs of degenerative hip joint changes are narrowing of the joint space due to thinning of the articular cartilage, subchondral sclerosis due to repair processes, osteophyte formation as a result of repair in nonweigthbearing, chiefly peripheral places, and the formation of subchondral cysts or pseudocysts due to bone contusions that cause microfractures and the leakage of synovial fluid into the altered cancellous bone (Fig. 4.25). Conventional X-rays show the different forms of destruction (Fig. 4.26).

Fig. 4.24. Right hip joint, a.p. view. Post-op inflammatory destruction of the femoral head with implant of Palacos beads, and additional pertrochanteric femoral fracture. Insertion of five wire loops around a longitudinal fissure in the proximal femur.

a

b

Fig. 4.25. Left hip joint, a.p. (a) and Lauenstein (b) views, in severe degenerative arthritis. Narrowing of the joint space

and reactive sclerosis of the corresponding articular surfaces, subchondral cysts and lateral osteophyte formation.

4 Abnormal radiographic anatomy of the proximal femur

]

Fig. 4.26. Severe, destructive degenerative arthritis of the left hip joint, deformity of the femoral head, and reactive sclerosis of the corresponding articular surfaces with narrowing of the joint space.

Fig. 4.27 a, b. Total body bone scan (a) in a case of marked degenerative arthritis of the left hip joint, and triple-phase

bone scan with anterior and posterior spot films of the left hip joint (b).

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B. Marquardt: 4 Abnormal radiographic anatomy of the proximal femur

References

Fig. 4.28. MR tomography of the pelvis: spin echo, T-1, with evidence of decreased signal in the region of the right femoral head due to microfractures in degenerative hip joint disease, and turbo-spin ehcho, T-2 weighted sequence, which now shows evidence of signal increase in the area of the multiple microfractures of the right femoral head.

In every instance where the radiographic findings are uncertain, a bone scan should be obtained for early diagnosis, including a triplephase skeletal study with separate views of the involved joint (Fig. 4.27). Figure 4.28 a, b show MR studies of a patient with right sided necrosis and microfractures of the femoral head. The coronal, T-1-weighted spin-echo view of the fracture area shows a diminished signal. A distinct signal increase is seen in the T-2-weighted coronal sequence.

1. Abt W, Jäger W (1983) quoted in: Dtsch Ärztebl 80:53–54 2. Bohndorf K, Imhof H (1995) Radiologische Diagnostik der Knochen und Gelenke. Thieme, Stuttgart 3. Delee J (1982) Fractures and dislocations of the hip. In: Rockwood CR, Green DP (eds) Fractures and Dislocations, Vol. II, 2nd ed. Lippincott, Philadelphia, pp 1211–1353 4. Dihlmann W, Heller M (1985) Asterisk-Zeichen und adulte ischämische Femurkopfnekrose. Fortschr Röntgenstr 142:430–435 5. Dittel KK, Felenda MR (1998) Operative Behandlung der Gelenk- und Schaftfrakturen – Die Verletzung der langen Röhrenknochen. Thieme, Stuttgart 6. Fielding JW (1973) Subtrochanteric fractures. Clin Orthop 92:86 7. Burgener FA, Kormano M (1997) Differentialdiagnose in der Computertomographie. Thieme, Stuttgart 8. Greenspan A (1990) Skelettradiologie: Orthopädie, Traumatologie, Rheumatologie, Onkologie. Übersetzt von Eduard M. Walthers. Ed. Medizin, Weinheim 9. McDonald EJ Jr, Goodman PC, Winestock DP (1975) The clinical indications for arteriography in trauma to the extremity. Radiology 116:45–47 10. Müller M (1980) Klassifikation und internationale AO-Dokumentation der Femurfrakturen. Unfallheilkunde 83:251–259 11. Nigst H (1972) Frakturen des proximalen Femurendes. In: Nigst H (Hrsg) Spezielle Frakturen und Luxationslehre, Bd. III. Thieme, Stuttgart, S 105– 120 12. Pauwels F (1976) Biomechanics of the Normal and Diseased Hip. Springer, New York 13. Pipkin G (1957) Treatment of grade IV fracturedislocation of the hip. J Bone Jt Surg 39-A:1027– 1042 14. Reiser M, Heller M (1984) Extremitätenverletzungen. In: Heller M, Jend HH (Hrsg) Computertomographie in der Traumatologie. Thieme, Stuttgart, S 106–116 15. Reiser M, Peters PE (Hrsg) (1995) Radiologische Differentialdiagnose der Skeletterkrankungen. Thieme, Stuttgart 16. Sauser DD, Bilimoria PE, Rouse GA, Mudge K (1980) CT evaluation of hip trauma. Amer J Roentgenol 135:269–274

Fracture classification at the proximal femur

5 Statistical items M. Rapp

Number of patients

600 500

Men Women Total

540 451

400 300

195

200

140 90

100 0

0 1 1

2 2 4

19 9 28

30) History of venous thromboembolic event

Table 18.3. Physical methods of prophylaxis in hip surgery (derived from Encke et al. 2003) Basic approaches

Additional methods

] Physiotherapy ] Early mobilisation ] Gradual compression stockings (carefully fitted)

] Early surgery for fracture to shorten duration of preoperative immobilisation ] Patient guidance on self-exercise ] Circulatory therapy ] Respiratory therapy ] Intermittent pneumatic leg compression ] Active and passive movements in the ankle

inhibits coagulation. An additive effect is hence generally expected by combining these prophylactic measures.

] Physical methods of prophylaxis Physical measures to prevent DVT in total hip replacement allow for a relative risk reduction of 20 to 70% which is less effective than current pharmacologic protocols (Geerts et al. 2004). Therefore, physical measures are commonly used to further decrease the thrombotic risk. Nonpharmacologic methods with effect on thrombotic risk are listed in Table 18.3.

] Pharmacological measures In patients with elective hip arthroplasty lowmolecular-weight heparins (LMWH), fondaparinux or Vitamin K antagonists were recommended by the seventh ACCP conference (Table 18.4). Whereas subcutaneous prophylaxis with

LMWH is preferred in Europe oral anticoagulation with Vitamin K antagonists is more commonly used in North America. A direct comparison with the LMWH dalteparin suggested the efficacy of Vitamin K antagonists to be significantly worse in hip surgery patients (Hull et al. 2000). Geerts et al. (2004) recommended against the use of low-dose unfractionated heparin (LDUH), aspirin and dextran as the only method to prevent thrombosis in hip arthroplasty. In hip fracture surgery, Geerts et al. (2004) mentioned LDUH in addition to the options listed in Table 18.4, and recommended LDUH or LMWH for prophylaxis in the period between admission to the hospital and hip fracture surgery if the procedure is likely to be delayed.

] Indications and dosing of various LMWH Before prescribing LMWH differences specific to the various preparations and to the approved indications/dosing regimen (see Summaries of Product Characteristics) should be considered

18 Prevention of venous thromboembolism in hip surgery

]

Table 18.4. Pharmacological prophylaxis in hip arthroplasty (derived from Geerts et al. 2004) Drug

Dose

First dose

] LMWH

Usual high-risk dose Usual high-risk dose Half the usual high-risk dose followed by an increase to the usual high-risk dose (next day)

12 h before surgery 12–24 h after surgery 4–6 h after surgery *

] Fondaparinux

2.5 mg

] Vitamin K antagonist

Adjusted, INR target 2.5 (range: 2.0 to 3.0)

6–8 h after surgery Preoperatively or the evening after surgery

* Alternative dosing regimen not mentioned by Geerts et al. (2004) which is registered in some countries for the LMWH dalteparin: Half the high-risk dose (2 500 anti-Xa U) 2 h before surgery, second dose 8 to 12 h after the first dose (earliest 4 h after surgery) followed by once daily high-risk dose (5 000 anti-Xa U) on the next days.

to avoid insufficient prophylaxis. For example, an inadequate daily dose of 2500 anti-Xa U dalteparin in high-risk procedures (abdominal surgery for malignancy) increased the incidence of DVT from 8.5 to 14.9% (p < 0.001) (Bergqvist et al. 1995). Certain LMWHs are registered with fixed dosages for prophylaxis, while the doses of others should be weight-adjusted in high-risk orthopaedic surgeries (Encke et al. 2003). Selecting a suitable LMWH and following the recommended dosage scheme are important contributory factors towards an optimized efficacy and tolerability of the prophylaxis.

] Pre-filled syringes versus multidose vials of LMWH On one hand, a single LMWH-dose is generally cheaper – in arithmetical terms – when taken from a multidose vial than from a pre-filled syringe. On the other hand, advocates of pre-filled syringes proclaim their dosage accuracy and fear a risk regarding safety when using multidose vials. A study was therefore conducted at the Hospital for Trauma Surgery of the Marienhospital Stuttgart, Germany (Rapp et al. 2001). In 1999, 273 patients undergoing surgery to the proximal femur were given high-risk prophylaxis with Fragmin® (dalteparin, daily dose: 5 000 anti-Xa U) from multidose vials. In the subsequent year prophylaxis was switched to dalteparin pre-filled syringes. After a further 170 patients a significant difference had already been revealed. Necessity for surgical revision of a haematoma was significantly reduced by the use of pre-filled syringes

(4.7% versus 10.6%, p < 0.05). VTE rate was 0.6% with pre-filled syringes versus 2.2% with multidose vials (p = n.s.). Therefore, the use of multidose vials may lead to relevant under- or overdosage.

] Duration of pharmacological thromboprophylaxis following hip surgery It has been demonstrated that a risk of thrombosis continues to exist until the 35th day postoperatively after hip replacement surgery. Phlebographic screening covering the period “day 7 to day 35” ascertained thrombosis rates of between 12% and 26% if pharmacological prophylaxis was not used following hospitalisation (Dahl et al 1997, Lassen et al. 1998). Hypercoagulability persisted for about 35 days and was significantly reduced by the LMWH dalteparin (Arnesen et al. 2003). Several studies confirmed the benefit of prophylaxis with LMWH or fondaparinux for 28 to 35 days after total hip replacement or hip fracture surgery (Bergqvist et al. 1996, Planes et al. 1996, Dahl et al. 1997, Lassen et al. 1998, Hull et al. 2000, Comp et al. 2001, Eriksson et al. 2003). An increased risk of bleeding was not seen from 35 days of LMWH application. Therefore, prolonged thromboprophylaxis for up to 28 to 35 days is recommended after total hip replacement or hip fracture surgery (Encke et al. 2003, Geerts et al. 2004). Another criterion for the duration of prophylaxis is the degree of mobility. The German Orthopaedic Association defined three prerequi-

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sites to be fulfilled before termination of prophylaxis (Pauschert et al. 1998): ] mobilisation for 4 to 6 hours per day ] partial load of leg ³ 20 kp ] free flexibility of the ankle joint

Relevant side effects of subcutaneous pharmacological prophylaxis in hip surgery Heparins have been investigated extensively with a view to side effects. It can basically be concluded that the incidence of side effects under LMWH is much lower than with unfractionated heparin.

] check for dosing errors ] determine anti-Xa level ] consider dose reduction or discontinuation of anticoagulant (and protamin for reversal of LMWH as an additional option). Injection haematomas represent a further, albeit only mild, side effect which is often felt by patients, however, to be stressful. After hip surgery the abdominal subcutaneous fatty tissue is to be favoured as the site of injection. Injection in the non-operated thigh would in fact also be possible, but in the event of more extensive bruising would lead to discomfort, which in the early mobilisation phase of the patient in particular would be undesirable.

] Heparin-induced thrombocytopenia ] Bleeding complications In patients undergoing hip surgery, prophylaxis with LMWH is generally well tolerated with regard to bleeding risk if recommendations listed in the summary of product characteristic (SmPC) are followed. An interval of about 12 hours between administration of a pre-OP highrisk dose of specific LMWH and the surgical intervention was defined to avoid an increase in bleeding risk (Bergqvist and Hull 2006). If an immediate surgical intervention is required, half of the high-risk dose may be administered preoperatively or prophylaxis may be started after surgery. Dosing regimens differ between LMWH. Therefore, surgeons may select an anticoagulant with dosing recommendations which fit to their needs in clinical practice. In patients with severe renal insufficiency treated with fondaparinux or specific LMWH bleeding risk may be increased due to a lack of dose adjustment. Physicians should be aware that LMWH are different preparations and differ with respect to the extent of their renal elimination (Stöbe et al. 2006, Tincani et al. 2006, Mahe et al. 2007). For example, a dose reduction by 25% to 30 mg/day is recommended in patients with creatinine clearance below 30 mL/min receiving enoxaparin for high-risk prophylaxis. In case of a bleeding complication during prophylaxis with LMWH or fondaparinux it is important to ] exclude surgical bleeding ] determine renal function

Heparin-induced thrombocytopenia type II (HIT II) is a life-threatening adverse drug reaction to heparin. A decrease of platelets can be explained by an antibody-mediated activation of platelets with subsequent thrombin generation, platelet aggregation and platelet consumption. Venous and/or arterial thromboembolic events may occur. Skin necroses may be another symptom of HIT II. The following findings during heparin administration or up to three weeks after cessation of heparin should lead to the suspicion of HIT II: ] drop in platelets by ³ 50% as compared to the peak postoperative value and/or ] new thromboembolic complication. Some Summaries of Product Characteristics (SmPC) for heparins state that HIT II is to be ruled out if platelet count falls below 100 000/ll. However, more recent data suggest that the percentage decrease is most relevant (Greinacher 2007). Algorithms for screening and diagnosis of HIT II may be useful to identify patients with HIT II (Warkentin and Greinacher 2007, Greinacher 2007). Non-immunological HIT (type I) may be considered in the event of a drop in platelets as well. The falls ensue from transient activation of the platelets in 5 to 30% of patients at the start of heparin therapy. Usually, the drop in platelets is lower than with HIT II. Further clinically remarkable events are not to be anticipated in HIT type I.

18 Prevention of venous thromboembolism in hip surgery

] Other side effects Heparin-induced osteoporosis is clinical important over long-term application of more than six weeks and was predominantly seen in patients treated with unfractionated heparin whereas the risk during long-term LMWH-prophylaxis is very low (Pettila et al. 2002, Rodger et al. 2007). Should there be a postoperative increase in transaminases and/or LDH in hip surgery patients, then differential diagnosis should include the consideration of heparin side effects. These laboratory values usually return to normal upon discontinuation of heparin. Such changes are not attributed clinical importance. Further side effects of heparins (e.g. pruritus, cutaneous efflorescences, etc.) are listed in the respective Summaries of Product Characteristics as well as side effects of fondaparinux and Vitamin K antagonists which are not mentioned here.

Forensic aspects of thromboprophylaxis Forensic matters play an outstanding role in thromboprophylaxis, as the consequences of thrombosis for the patients can be severe (e.g. post-thrombotic syndrome or fatal pulmonary embolism). Frequent sources of error are as follows: ] insufficient prophylactic measures (e.g. ASA) ] too short a period of prophylaxis ] too low a dose of anticoagulant ] the patient being provided with inadequate explanations ] misinterpretation of clinical symptoms of thrombosis ] inadequate diagnosis of thrombosis ] inadequate screening for HIT II (Haas 1998)

References 1. Arnesen H, Dahl OE, Aspelin T, Seljeflot I, Kierulf P, Lyberg T (2003) Sustained prothrombotic profile after hip replacement surgery: the influence of prolonged prophylaxis with dalteparin. J Thromb Haemost 1:971–975

]

2. Bergqvist D, Burmark US, Flordal PA, Frisell J, Hallbook T, Hedberg M, Horn A, Kelty E, Kvitting P, Lindhagen A et al (1995) Low molecular weight heparin started before surgery as prophylaxis against deep vein thrombosis: 2500 versus 5000 Xa units in 2070 patients. Br J Surg 82:496– 501 3. Bergqvist D, Benoni G, Bjorgell O, Fredin H, Hedlundh U, Nicolas S, Nilsson P, Nylander G (1996) Low-molecular-weight heparin (enoxaparin) as prophylaxis against venous thromboembolism after total hip replacement. N Engl J Med 335:696–700 4. Bergqvist D, Hull RD (2006) Effective thromboprophylaxis administered close to the time of major orthopedic surgery: a review. Am J Orthop 226–230 5. Comp PC, Spiro TE, Friedman RJ, Whitsett TL, Johnson GJ, Gardiner GA, Landon GC, Jove M (2001) Prolonged enoxaparin therapy to prevent venous thromboembolism after primary hip or knee replacement. Enoxaparin Clinical Trial Group. J Bone Joint Surg Am 83:336–345 6. Dahl OE, Andreassen G, Aspelin T, Muller C, Mathiesen P, Nyhus S, Abdelnoor M, Solhaug JH, Arnesen H (1997) Prolonged thromboprophylaxis following hip replacement surgery – results of a double-blind, prospective, randomised, placebocontrolled study with dalteparin (Fragmin). Thromb Haemost 77:26–31 7. Encke A, Haas S, Krauspe R, Riess H, Stürmer KM (2003) Stationäre und ambulante Thromboembolie-Prophylaxe in der Chirurgie und der Perioperativen Medizin. Beilage zu den Mitteilungen der Deutschen Gesellschaft für Chirurgie, G97 8. Eriksson BI, Kalebo P, Anthymyr BA, Wadenvik H, Tengborn L, Risberg B (1991) Prevention of deep-vein thrombosis and pulmonary embolism after total hip replacement. Comparison of lowmolecular-weight heparin and unfractionated heparin. J Bone Joint Surg Am 73:484–493 9. Eriksson BI, Lassen MR, the PENTasaccharid in HIp-FRActure Surgery Plus (PENTHIFRA Plus) Investigators (2003) Duration of prophylaxis against venous thromboembolism with fondaparinux after hip fracture surgery: a multicenter, randomized, placebo-controlled, double-blind study. Arch Intern Med 163:1337–1342 10. Geerts WH, Pineo GF, Heit JA, Bergqvist D, Lassen MR, Colwell CW, Ray JG (2004) Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest 126 (3 Suppl):338S–400S 11. Greinacher A (2007) Lepirudin in clinical practice. Refludan® (lepirudin) in acute HIT, 1st ed. Socio-medico, Wessobrunn, ISSN 1864-7219 12. Hass S (1998) Medizinische Grundlagen und medico-legale Aspekte der venösen Thromboembolieprophylaxe. Chirurg BDC 37:242–250

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13. Hull RD, Pineo GF, Francis C, Bergqvist D, Fellenius C, Soderberg K, Holmqvist A, Mant M, Dear R, Baylis B, Mah A, Brant R (2000) Low-molecular-weight heparin prophylaxis using dalteparin extended out-of-hospital vs in-hospital warfarin/ out-of-hospital placebo in hip arthroplasty patients: a double-blind, randomized comparison. North American Fragmin Trial Investigators. Arch Intern Med 160:2208–2215 14. Hull RD, Pineo GF, Francis C, Bergqvist D, Fellenius C, Soderberg K, Holmqvist A, Mant M, Dear R, Baylis B, Mah A, Brant R (2000) Low-molecular-weight heparin prophylaxis using dalteparin in close proximity to surgery vs warfarin in hip arthroplasty patients: a double-blind, randomized comparison. The North American Fragmin Trial Investigators. Arch Intern Med 160:2199–2207 15. Lassen MR, Borris LC, Anderson BS, Jensen HP, Skejo Bro HP, Andersen G, Petersen AO, Siem P, Horlyck E, Jensen BV, Thomsen PB, Hansen BR, Erin-Madsen J, Moller JC, Rotwitt L, Christensen F, Nielsen JB, Jorgensen PS, Paaske B, Torholm C, Hvidt P, Jensen NK, Nielsen AB, Appelquist E, Tjalve E et al (1998) Efficacy and safety of prolonged thromboprophylaxis with a low molecular weight heparin (dalteparin) after total hip arthroplasty – the Danish Prolonged Prophylaxis (DaPP) Study. Thromb Res 89:281–287 16. Mahe I, Aghassarian M, Drouet L, Dit-Sollier CB, Lacut K, Heilmann JJ, Mottier D, Bergmann JF (2007) Tinzaparin and enoxaparin given at prophylactic dose for eight days in medical elderly patients with impaired renal function: a comparative pharmacokinetic study. Thromb Haemost 97:581– 586 17. Pauschert R, Diehm C, Stammler F (1998) Guidelines for prevention of thrombosis in orthopedics [Leitlinien zur Thromboseprophylaxe in der Orthopädie]. Z Orthop Ihre Grenzgeb 136:471–479 18. Pettila V, Leinonen P, Markkola A, Hiilesmaa V, Kaaja R (2002) Postpartum bone mineral density

19.

20.

21.

22.

23.

24. 25.

in women treated for thromboprophylaxis with unfractionated heparin or LMW heparin. Thromb Haemost 87:182–186 Planes A, Vochelle N, Darmon JY, Fagola M, Bellaud M, Huet Y (1996) Risk of deep-venous thrombosis after hospital discharge in patients having undergone total hip replacement: doubleblind randomised comparison of enoxaparin versus placebo. Lancet 348:224–228 Rapp M, Felenda M-R, Dittel K-K (2001) Thromboprophylaxis by low-molecular-weight heparin (Fragmin*) in surgery at the proximal femur – a comparative study of multidose vials versus syringes (Abstract). 8th International Symposium on Thromboembolism, Florenz/Italien, Abstrakt Band, S 37 Rodger MA, Kahn SR, Cranney A, Hodsman A, Kovacs MJ, Clement AM, Lazo-Langner A, Hague WM (2007) Long-term dalteparin in pregnancy not associated with a decrease in bone mineral density: substudy of a randomized controlled trial. J Thromb Haemost 5:1600–1606 Stöbe J, Siegemund A, Achenbach H, Preiss C, Preiss R (2006) Evaluation of the pharmacokinetics of dalteparin in patients with renal insufficiency. Int J Clin Pharmacol Ther 44:455–465 Tincani E, Mannucci C, Casolari B, Turrini F, Crowther MA, Prisco D, Cenci AM, Bondi M (2006) Safety of dalteparin for the prophylaxis of venous thromboembolism in elderly medical patients with renal insufficiency: a pilot study. Haematologica 91:976–979 Warkentin TE, Greinacher A (2007) Heparin-induced thrombocytopenia, 4th ed. revised and expanded. Marcel Dekker, New York Basel White RH, Gettner S, Newman JM, Trauner KB, Romano PS (2000) Predictors of rehospitalization for symptomatic venous thromboembolism after total hip arthroplasty. N Engl J Med 343:1758– 1764

19 Physiotherapy after surgery for proximal femur fractures R. Plank

Any postoperative deep venous thrombosis, in the worst case in connection with thromboembolism, can be described as the most serious complication and the leading cause of death in orthopaedic and trauma surgery. The incidence of postoperative deep venous thrombosis according to the late literature can be found between 5 and 20% in the specific patient group (according to own experiences). Clinical relevant lung embolism is found between 1 and 2% after orthopaedic and trauma surgery in the hip joint area (according to own experiences). These facts show that every postoperative thrombosis until our days still remains a threatening problem with possible disastrous consequences. Thromboprophylaxis is necessary in all situations when reduction of mobility takes place. Therefore prophylactic measures are necessary in connection with any type of immobilisation under critical indication. Early operative procedures and early mobilisation can help to reduce the risk of the event of a thrombosis as well as the invitation to the patient to start and to continue with own exercises, which should be demonstrated to him. Low dose heparin medicamentation does not always guarantee a sufficient reduction of the risk of a thrombosis. Therefore the low molecular heparins have better pharmaceutical characteristics giving the patient and the doctor a better protection in the high risk area in trauma and emergency as well as elective operations. The physiotherapist is the best ally of the orthopaedic surgeon in almost all cases because an effective physiotherapy guarantees the reduction or the avoidance of a broad spectrum of complications and disabilities by an adequate and comprehensive physiotherapeutic follow up treatment.

Pre-surgical Often pre-surgical evaluation and instruction by a physiotherapist is not possible, if the surgery is not planned ahead. Young people have accidents in sports or other leisure time activities. The neck of femur also breaks because of recurrent microtrauma. Elderly people often fall and in many cases the neck of femur breaks because of a spontaneous osteoporotic fracture. Apart from the psychological stress of the accident and the strange situation in hospital, in older patients physical strength strongly influences the recovery. After surgery older people are often confronted with too much, are not flexible, and react apathetically about the new situation. Because of that physiotherapists should counteract the impaired coordination of movement, the diminished abilities of memory and concentration and the decreased strength, coordination and stamina with appropriate and creative exercises. In order to achieve a good relationship between the therapist and the patient one should avoid expecting too much or to little during therapy. The following 10 points have positive influence to motivate the patient to a good cooperation: For the treatment: 1. Clear instructions 2. Keep eye contact 3. Patience 4. Take enough time 5. Simple exercises of short duration 6. Exercises in painless range 7. Sufficient breaks (watch for breathing, blood pressure and pulse) 8. Sufficient repetitions 9. Easy program for home exercises 10. Exercises for daily routine and occupation.

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If a pre-surgical evaluation for physiotherapy is possible, some measures which are important after surgery should be pointed out to the patients. It would be ideal to explain and practice the exercises with the patients before surgery. ] Breathing exercises ] Precaution against thrombosis ] Practice walking on forearm crutches (correct length of crutches!) ] General rules how to behave in daily routine (for example resting up legs) ] One-sided bridging (as a pre-exercise for hygiene of the body).

Surgery As mentioned in the previous chapter. Often conditions like anesthesia, pain of the wound, hematoma, edema, muscles spasm and the drainage lead to problems and restrictions at the first days after surgery.

Prescribing physiotherapy and physical therapy Physiotherapy (x) Physiotherapy (x) Breathing exercises (always in elder patients and patients in reduced state of health) ( ) State of strain

( ) stable in movement ( ) stable in exercise (x) stable on weight bearing

(x) Walking practice ( ) touch down from leg with no weight (x) weight bearing with 20 kg ( ) full weight bearing ( ) CPM range of motion Joint degree // (x) lymphatic drainage/pressure bandage (if effusion, swelling . . .)

Group ( ) hip training (possibly) ( ) physiotherapy in the water, water walking in pool (after stitch-removal). Physical therapy (x) ice (twice a day) ( ) electrotherapy (if severe hematoma).

Early physiotherapy At the first day after surgery the patient is treated passively in bed, if possible actively with assistance. The treatment focuses on the quadriceps muscle and the abductor muscles, which are the first to atrophy and therefore have to be given priority in the treatment. All of the four muscle groups at the thigh should have a grade of strength of three, which means holding the specific weight of the leg. In early treatment it should be stressed that all the exercises are done in painless range or with little pain. One always has to pay attention to the patient’s subjective sensation of pain. Pain after stitch-removal or drainage is tolerable. At the same time special emphasis should be given to the reduction of hematoma and the elimination of edema (after removal of drainage ice up to twice a day). If one stick to the rules mentioned above one can achieve the best possible contraction of the muscle and function is therefore optimized. The interplay between the muscle, osteosynthesis, and the load-carrying capacity of the femur should be well balanced in comparison to the weight bearing. If this is not possible to achieve, pain, guarding, avoiding movements, limping, and osteoporosis of the bone might occur, so that the patient is hardly motivated to move at all. Most commonly the surgeon prescribes weight bearing of 20 kg. The patient is only able to keep to this weight bearing of 20 kg properly, if the interplay of the four muscle groups of the thigh and of the leg work perfectly, a grade of strength of three is achieved and if the patient is reasonably pain-free and able to move. Properly adjusted forearm crutches and the practice of a “three-point-gait” are necessary.

19 Physiotherapy after surgery for proximal femur fractures

If possible get patient out of bed in a chair (with a higher seat) postoperative at first day. To control the desired weight bearing, the patient can walk in “three-point-gait” with his crutches on a scale on the ground. While walking, this weight bearing can not be kept up if the patient lacks strength in the upper arm to put his own weight on the forearm crutches. Bergmann et al. (1989) wrote about different stress on the hip in different positions. “There is a stress of 30% of the body weight in sitting position. While getting up from a chair without support of hands up to 220%; with support of hands 110%, while putting weight on both legs about 70% and while walking up to 300% of body weight.” These functional factors are of great importance for mechanical stability in physiotherapy “While doing active exercises against resistance in lying position strains on the hip joint up to 280% of body weight and while doing supportive exercises strains up to 50% of body weight are reached. With forearm crutches the strain can be decreased by 25%.” The stability in exercises depends upon putting a reasonable load, muscle tension, and body weight on the osteosynthesis and uses it sensibly. Furtheron the weight bearing can be increased symptomatically by about 5 kg per week, when there is improvement of the muscle function, mobility and coordination. By the 7th week, full weight bearing on the affected leg should be achieved (rehabilitation, “AHB”, outpatient treatment).

Therapeutic exercises ] Day after surgery a) Precaution against pneumonia Respiratory intensification by the temporary immobilization is supported by: ] guided breathing ] perception of breathing (“Basaltexte, Schaarschuch-Haase”) ] change of position ] special devices (Monoflow, Triflow) ] movement (passive, active).

]

b) Precaution against thrombosis Normally by intensive stepping exercises (or ankle pumps) (dorsal extension, plantar flexion) practiced with the patient: ] resting the leg in high position ] compression (stockings or bandage against thrombosis). In most cases the affected leg is dressed with a bandage up to the thigh until the drainage is removed. After removal of the drain, the bandage is replaced by stockings against thrombosis (best possible size up to the thigh): – static exercises for tension – movement (passive/active). Relating to a) and b): both points play a higher role in the first days after surgery. These measures should be attached great importance until the patient becomes “active” 2/3 of the day. c) Precaution against decubitus Most of the times it is not necessary because of the patient is mobilized early. Nevertheless keep an eye on the heel of the operated leg. d) Precaution against hematoma ] ice twice a day for 15 min ] resting the leg in high position ] compression (bandage, stockings thrombosis) ] lymphatic drainage.

against

e) Mobilisation ] supported parallel bars walking gives safety and stability at the first day after surgery ] from the 2nd/3rd day after surgery walking exercises with forearm crutches or walker.

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Examples (in these examples the left leg is operated) ] 2 days after operation 1.

Patient in bed on the back Lying with heel supported gently curl and straighten toes. Avoid pain. Repeat 5–10 times. Do 2 sets per session. Do 5–10 sessions per day.

2.

Relax leg. Gently bend and straighten ankle. Move through full range of motion. Avoid pain. Repeat 5–10 times. Do 2 sets per session. Do 5–10 sessions per day.

3.

Slowly rotated foot and ankle clockwise and counterclockwise. Gradually increase range of motion. Avoid pain. Repeat 5–10 times. Do 2 sets per session. Do 5–10 sessions per day.

4.

Tighten buttock muscles. Hold 2 seconds. Avoid pain. Repeat 5–10 times. Do 2 sets per session. Do 5–10 sessions per day.

5.

Extending toes toward knee, tense muscles on front of tight and simultaneously squeeze buttocks. Keep leg and buttock flat on bed. Hold 2 seconds. Avoid pain. Repeat 5–10 times. Do 2 sets per session. Do 5–10 sessions per day.

19 Physiotherapy after surgery for proximal femur fractures

6. Gently bring leg on of side and tense leg muscles toward outside, inside and up. No movements. Cocontraction. Avoid pain. Repeat 5–10 times. Do 2 sets per session. Do 2 times a day.

7.

8.

Place rolled towel under knee. Bend knee over and straighten. Hold for 2 seconds and slowly lower. Avoid pain. Repeat 5–10 times. Do 2 sets per session. Do 2 times a day.

Tighten stomach muscles, then slowly lift leg 6–12 inches from the bed. With PT help! Keeping knee straight. Avoid pain. Repeat 5 times. Do 2 sets a session. Do 2 sessions a day.

]

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9. With resisted band around hands, bring one arm up/down and across body. Strengthening from the arms is important for walking. Repeat 5–10 times. Do 2 sets a session. Do 2 sessions a day.

1.

] After 3–10 days Tighten stomach muscles, bend non operated leg backward towards buttock, slide heeling. The same with operated leg. Avoid pain. Repeat 5–10 times. Do 2 sets a session. Do 2 times per day. ] Variation: ball under heel and leg. Bending at and hip. Avoid pain. ] Variation: bend both knees and hips. Feltenkrais Clock for pelvis movements. ] Variation: slowly raise buttock from floor. Keeping stomach tight. Bridging. Avoid pain.

19 Physiotherapy after surgery for proximal femur fractures

2.

3.

4.

5.

]

From lying position. Extend legs and feet and push them toward end of bed leg by leg. Extend also arms and hands. Avoid pain. Repeat 5–10 times. Do 5 sets a session. Do 2 times per day.

Gently pull knee from non operated leg to the chest. Operated leg should be staying down. As picture shown. Until stretch is felt. Hold 2 seconds. Avoid pain. Repeat 5–10 times. Do 2 times per day.

Patient of belly: With pillow supporting abdomen, and forehead resting on towel roll. Stay on toes and raise backside of knees towards roof. Breath! Avoid pain. Repeat 5 times. Do 2 times per day.

From lying position, have PT gently help raise leg with bended knee. Until stretch. Hold 2 seconds. Avoid pain. Repeat 5 times. Do 2 times per day.

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6. From lying position as in 4. Keep knee locked and have PT to raise leg up. And opposite arm 6–8 inches from floor. Breath! Avoid pain. Repeat 5 times. Do 2 times per day.

7. Lie on bed as shown. Raise leg from floor towards your chest and arch your back. Repeat 5 times. Do 2 times per day.

8. Patient of non-operated side: Lying on side with pillow between tights, have PT to help raise top leg from pillow, rotating it slightly outward. Hold 2 seconds. Avoid pain. Repeat 5 times. Do 3 sets a session. Do 2 times per day. Variation: with knee extension and knee bending.

19 Physiotherapy after surgery for proximal femur fractures

9.

Patient sitting on chair: Raise heel off floor, keeping toes on floor. Raise toes and keeping heel on floor. Avoid pain. Repeat 5–10 times. Do 3 sets a session. Do 3 times per day.

10. Knee 6–8 inches up from floor. Avoid pain. Repeat 5 times. Do 3 times per day.

]

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11. Sitting, straighten leg, hold and slowly lower. Avoid pain. Repeat 5 times. Do 3 times per day.

The varieties of exercises are examples for therapy. It is not necessary to do all the exercises with the patient. It is the therapist’s duty to choose the appropriate specific exercises for each individual patient. Also the repetition of the exercises and the times per day has to be adjusted to the abilities of the patient. Avoiding pain is very important. The patient is always right! If it is possible the therapist should discuss over a home program of exercises.

References Bergmann G, Rohlmann H, Graichern F (1989) In vivo Messung am Hüftgelenk Bonnaire F (1991) Experimentelle Untersuchungen zum Stabilitätsverhalten am koxalen Femurende nach Montage und Entfernung von DHS Implantaten am nicht frakturierten Leichenbefund. Unfallchirurg, S 366–371 Hermichen HG, Wintermann S (2001) Gut leben mit dem neuen Hüftgelenk. Trias, Stuttgart Kolster B (1996) Leitfaden Physiotherapie, S 322–348 Jerosch J, Heisel J (2001) Künstlicher Gelenkersatz, S 168–196 Aebi-Müller J, Gloor-Moriconi I, Koch P (1997) Funktionelle Nachbehandlung von Patienten mit künstlichem Hüftgelenk, S 28–56

20 Operative revisional management M. Rapp, K.-K. Dittel

Revisional management case 20.1

Complication: subtrochanteric pseudarthrosis

74 years old female

Subtrochanteric femur fracture, AO classification 32 B 2-1 Osteosynthesis by proximal femur nail (PFN) Subtrochanteric femur pseudarthrosis and implant failure after repeated fall Implant removal and reosteosynthesis by 9-hole condylar blade plate and additional autogenous spongy plasty Delayed fracture healing and varus malposition of the proximal fragment Implant removal, valgisation osteotomy and reosteosynthesis by 6-hole DMS

Fig. 20.1.1. Day of accident.

Fig. 20.1.2. Pop. x-ray check.

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Fig. 20.1.3. Subtrochanteric femur pseudarthrosis and implant failure.

Fig. 20.1.4. Pop. check after implant removal and reosteosynthesis by 9-hole condylar blade plate and additional autogenous spongy plasty.

Fig. 20.1.5. Delayed fracture healing and varus malposition 3 months after reosteosynthesis.

Fig. 20.1.6. Implant removal, valgisation osteotomy and reosteosynthesis by 6-hole DMS.

Fig. 20.1.7. X-ray check after 3 months.

Fig. 20.1.8. X-ray check after 6 months.

20 Operative revisional management

Revisional management case 20.2 Complication: implant cutting out of the head neck fragment

79 years old female

Intertrochanteric femur fracture, AO classification 31 A 2-3 Osteosynthesis by 4-hole DMS Lag screw cutting out of the head neck fragment after 2nd bang Implant removal and implantation of a cemented hip prosthesis

Fig. 20.2.1. Day of accident.

Fig. 20.2.2. Pop. x-ray check.

Fig. 20.2.3. Lag screw cutting out of the head neck fragment after 2nd bang.

Fig. 20.2.4. Pop. x-ray check after implant removal and implantation of a cemented hip prosthesis (Bicontact).

]

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Revisional management case 20.3 Complication: femur head perforation by the lag screw

89 years old female

Intertrochanteric femur fracture, AO classification 31 A 3-3 Osteosynthesis by 6-hole DMS Femur head perforation after full weight bearing Implant removal and implantation of a cemented tumor prosthesis

Fig. 20.3.1. Day of accident.

Fig. 20.3.2. Pop. x-ray check.

Fig. 20.3.3. Femur head perforation by the lag screw.

Fig. 20.3.4. X-ray check after implant removal and implantation of a cemented tumour prosthesis.

20 Operative revisional management

Revisional management case 20.4 Complication: femur head necrosis

76 years old female

Medial femur neck fracture, AO classification 31 B 1-3 Osteosynthesis by 2-hole and additional intertrochanteric lag screw Femur head necrosis 15 weeks after primary stabilization Implant removal and implantation of a cemented hip prosthesis

Fig. 20.4.1. Day of accident.

Fig. 20.4.2. Pop. x-ray check.

Fig. 20.4.3. Femur head necrosis 15 weeks pop.

Fig. 20.4.4. Pop. x-ray check after implant removal and implantation of a cemented hip prosthesis (Bicontact).

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Revisional management case 20.5 Complication: Implant dislocation at the femur shaft

84 years old female

Intertrochanteric femur fracture, AO classification 31 A 2-2 Enclosed arthrodesis nail at the knee joint Osteosynthesis by 4-hole DMS Implant dislocation by 2nd bang Reosteosynthesis by a 14-hole DMS

Fig. 20.5.1. Day of accident.

Fig. 20.5.2. Pop. x-ray check.

Fig. 20.5.3. Implant dislocation 4 weeks pop. (second bang).

Fig. 20.5.4. Pop. x-ray check after reosteosynthesis by 14-hole DMS.

20 Operative revisional management

Revisional management case 20.6 Complication: Primary malpositioned supporting screw – secondary cutting out

29 years old male

Intertrochanteric reversed femur fracture, AO classification 31 A 3-3 Osteosynthesis by 8-hole DMS plate and intraoperative valgisation Secondary cutting out because of primary malpositioned supporting screw Reosteosynthesis by 8-hole DMS

Fig. 20.6.1. Day of accident.

Fig. 20.6.2. Pop. x-ray check.

Fig. 20.6.3. Continuously secondary cutting out.

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Fig. 20.6.4. Pop. x-ray check after reosteosynthesis.

Fig. 20.6.6. X-ray check after 16 months and after implant removal.

Fig. 20.6.5. X-ray check after 12 months.

21 Evidence-based drug treatment of osteoporosis K. K. Förster, K. M. Peters

Introduction Osteoporosis is a common age-related bone deterioration associated with a slow loss of cortical and trabecular bone in men and women. It usually starts in the fourth or fifth decade. Years of bone loss follow a dysbalance between bone resorption and bone formation, and cortical and trabecular bone loss accelerate in women after menopause leading to osteoporosis (Figs. 21.1 and 21.2). Osteoporosis literally means “porous bone” and involves skeletal fragility leading to an increased risk of fracture, due to a microarchitectural deterioration of bone tissue. Osteoporosis is probably the most common metabolic disease in the world becoming an increasing public health problem in most countries (Sambrook

a

Fig. 21.1. a Severe osteoporosis with multiple vertebral fractures. b DHS stabilization of a pertrochanteric femur frac-

and Cooper 2006). According to a consensus statement published in 2000 the NIH defines osteoporosis as a “skeletal disorder characterized by compromised bone strength, with predisposition to an increased risk of fracture”. The World Health Organization describes osteoporosis as a metabolic disorder with a bone density of 2.5 SD below the mean for young adult white women with an age of 25 to 30 years (Table 21.1). Cautiously estimated, in Germany osteoporosis occurs in about 6–8 million women and men, resulting in at least 0.4 million fragility fractures per year. The German “Guidelines for Prophylaxis, Diagnosis and Therapy of Osteoporosis” have contributed much to our understanding of primary osteoporosis in postmenopausal women and older men (DVO-Guidelines 2006). Low mineral density predicts fractures in all races, but fracture risks are different between

b

c

ture on the right in osteoporosis. c Right distal femur fracture in osteoporosis adjusted by an angle plate.

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Table 21.2. Association of osteoporosis with other diseases and disorders (according to Lindsay et al. 1996) ] Diseases Anorexia nervosa, cystic fibrosis, hepatic insufficiency, homocystinuria, inflammatory bowel disease, mastocytosis, celiac disease, multiple myeloma, osteogenesis imperfecta, rheumatoid arthritis, sarcoidosis, Waldenström’s macroglobulinemia ] Endocrine disorders Cushing’s syndrome, diabetes mellitus type I and II, hypogonadism, hyperparathyroidism, hyperthyroidism ] Immobilization Extended bed rest, lengthy casting or splinting, paralysis, routine inactivity, sedentary life style ] Chronic drug therapy Heparin, warfarin, anticonvulsants, corticosteroids, cyclosporine, methotrexate, vitamin A and certain synthetic retinoids, anxiolytics, neuroleptic drugs

Fig. 21.2. Multiple fish vertebrae in osteoporosis. Table 21.1. Diagnostic criteria for osteopenia and osteoporosis based on bone mass measurements Bone mass ] Normal

A value for bone mineral density (BMD) with one standard deviation (SD) of the young adult reference mean

] Low bone mass A value for BMD > 1 and < 2.5 SDs below the young adult reference mean (osteopenia) ] Osteoporosis

A value for BMD > 2.5 SDs below the young adult reference mean

] Severe osteoporosis

A value for BMD > 2.5 SDs below the young adult reference mean in the presence of one or more fractures

ethnic groups. White postmenopausal women are at highest risk for osteoporosis and related fractures. Three-fourths of hip fractures are found in this group, especially at an age of 70 years or higher. Hip fracture rates are lower in men and Afro-American women, Hispanic women, Asians and Native Americans. Osteoporosis is a complex disorder with various subtypes of different etiopathogenetic causes (Keck and Kruse 1994). There is a common association with other diseases (Table 21.2) and a large array of risk factors which may overlap (Table 21.3).

Table 21.3. Risk factors for osteoporosis (according to Sambrook et al. 1994, Lane and Leboff 2005, Fulton 1999, Natl. Osteoporosis Foundation 2003) Primary risk factors ] Female sex, previous fracture at < 50 years, parent or sibling with previous fractures ] Low body weight < 58 kg or height > 1.70 m ] Female sex. Estrogen deficiency. Menopause before age 45 years or bilateral ovariectomy ] Prolonged premenopausal amenorrhea > 1 year Secondary risk factors ] Nonmodifiable white race, advanced age, frailty or poor health, dementia ] Modifiable lifestyle factors, low calcium intake, eating disorder, low testosterone levels in men, premenopausal estrogen deficiency, excessive alcohol intake, physical inactivity, impaired vision, neurologic disorders, lack of sunlight exposure, recurrent falls

Prevention and treatment of osteoporosis Reductions in bone mass are more easily prevented than treated. The older the patient, the less is the individual bone mineral content. The same holds true for the earlier menopause. The majority of female patients are candidates for

21 Evidence-based drug treatment of osteoporosis

some measures of prophylaxis. The earlier we intervene with bone-conserving tactics, the better the outcome is likely to be. As it is well-known, malnutrition is detrimental to skeletal health, it should be corrected whenever possible. Therefore, the first step in the prevention of osteoporosis involves adequate nutrition, particularly maintaining adequate calcium and vitamin D intake. This is important for individuals of all ages. Physical activity also has a beneficial effect on bone integrity thus increasing the peak bone mass in the young individual. Specific bone stimulating exercise regimens have not yet been clearly identified, but a reasonable approach is to encourage daily weight-bearing and gravity influenced aerobic exercise. Immobility presents a major risk for fractures of the proximal femur and vertebral bones. Another risk factor in men and in women is a low body mass. The prevention of calcium depletion is being stressed. A simple approach, consisting in supplementation of calcium and vitamin D, has been shown to reduce the risk of fracture in an earlier study of women with an average age of 84 years (Chapuy et al. 1992). Estrogen replacement therapy at menopause is suggested, particularly for women with decreased bone mass and hormone imbalance. This measure in women has been clearly demonstrated to be associated with fewer extravertebral fractures and greater bone density.

Table 21.4. Techniques for bone density measurements

] Screening for osteoporosis and evaluation of treatment efficacy

] Calcium supplementation

Screening for osteoporosis is justified for the following reasons: The disease is common and associated with a high morbidity and mortality. Based on accurate and safe diagnostic tests the diagnosis and, moreover, an intervention threshold is readily made. An effective and rather safe treatment is available. In addition, screening tests to measure bone density are necessarily needed to predict the outcome of treatment and control patient compliance. Dual x-ray absorptiometry (DXA) is the most popular method for measuring bone density because it gives relatively precise and quick measurements at clinically important sites with low costs. It addresses, however, not all bone impacts (i.e., microarchitecture, matrix factor, ge-

]

] Plein radiographs can demonstrate osteopenia. The sensitivity is low ] Single-photon absorptiometry (SPA). Can only be used at peripheral sites (radius, calcaneus) ] Dual-photon absorptiometry (DPA): Allows to measure bone density at clinically important sites (spine, hip) ] Dual x-ray absorptiometry (DXA). Gives precise measurements at clinically important sites ] Quantitative computed tomography (QCT). Is an accurate method to measure spinal bone density. It requires a higher radiation dose than DXA and is expensive ] Quantitative ultrasonography. Does not measure bone mineral content directly. It is a good predictor of fracture risk

ometry). Table 21.4 shows the present techniques available to measure bone density. Measurement of markers for bone turnover may potentially be useful in predicting rates of bone loss (Eastell et al. 2001). The mean values for biochemical markers of bone turnover seem higher in patients with osteoporosis than in normal persons. Urinary deoxypyridinoline and N-telopeptides of collagen are sensitive in detecting moderate and substantial increases in bone resorption associated with postmenopausal osteoporosis. Serum osteocalcin concentrations are sensitive markers of decreased bone formation in patients with primary postmenopausal disease or secondary osteoporosis.

Calcium is an essential nutrient that is involved in most metabolic processes together with the phosphate salts which in proper correlation provide mechanical rigidity to the bone (Nordin 1997). Multiple therapeutic regimens have been designed to prevent bone loss in postmenopausal women and the elderly. Studies showed that the calcium balance is related to calcium intake and an adequate calcium intake reduces bone loss in adults. In the elderly calcium and vitamin D reduce the rate of bone loss and decrease fracture risk (Chapuy et al. 1992). In postmenopausal women with a low calcium intake less bone was lost when calcium was supplemented. 1000 mg/day calcium supplementation prevented the decrease in hip bone density that occurs in the winter in elderly New

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York and England women. Calcium supplementation in individuals over the age of 65 years demonstrated similar benefits. Most studies have been performed in postmenopausal women, but older men also seem to benefit from calcium supplementation. The recommended daily calcium intake in premenopausal women and in men is 1000 mg/ day. In postmenopausal women who do not take estrogen, the intake of calcium should be 1500 mg/day (NIH 1994). Calcium supplementations (mostly recommended as calcium citrate which is better absorbed than calcium carbonate even when taken with meals) are not less effective than calcium from natural dairy products. If the total calcium intake routinely exceeds 2000 mg/day there may occur possible adverse effects like dyspepsia and constipation. Calcium supplementation taken with meals reduces iron absorption from food leading to possible iron deficiency anemia. There is a small risk for renal stones in women with a history of nephrolithiasis. These women should take calcium supplementation with meals. Calcium supplementation is not enough to replace postmenopausal bone loss as effectively as a hormone substitution with estrogen-gestagen (Wüster 1995).

] Vitamin D Overt symptoms of vitamin D deficiency, characterized biochemically by hypocalcemia or hypophosphatemia, and clinically by rickets or osteomalacia, are uncommon in most developing countries. Subclinical vitamin D deficiency (serum level below 30–50 ng/ml), however, is common and may contribute to the development of osteoporosis in older people. Approximately one-half of elderly women consume less than 137 IU/day vitamin D. In addition, intestinal resistance to 1,25-dihydroxyvitamin D and limited renal activation may contribute to the negative calcium balance in the elderly. Since calcium absorption is normally stimulated by vitamin D, the defect in osteoporosis could reflect vitamin D deficiency or resistance. Postmenopausal women with low serum concentrations of vitamin D have lower bone mineral density than those with normal or high concentrations. A positive association between serum vitamin D levels and bone mineral den-

sity has been reported (Bischoff-Ferrari et al. 2004). A third of patients with hip fractures have histological evidence of osteomalacia, the classic manifestation of vitamin D deficiency. These observations and the majority of clinical trials suggest that physiologic doses of vitamin D may protect bone by preventing bone loss and healing subclinical osteomalacia. Consequently, in elderly women assigned to treatment with 800 IU vitamin D and 1200 mg calcium a day versus placebo, hip bone density increased in the treated women with a significant lower fracture rate (Chapuy et al. 1992). In men and women over the age of 65 years the combination of 500 mg calcium and 700 IU vitamin D/ day improved bone mineral density and decreased the risk of nonvertebral fractures. A meta-analysis of several randomized, controlled studies of elderly persons (mean age 79 years) treated with 400 IU/day low-dose vitamin D versus 700–800 IU/day higher-dose vitamin D showed that the higher dosis vitamin D reduced the relative risk of hip and nonvertebral fractures. No significant fracture benefit was seen with the low-dose vitamin D treatment (Bischoff-Ferrari 2005). In addition to its effect on bone mineral density, vitamin D supplementation is also proven to reduce fracture risk by improving muscle function and decrease the risk of falls. An even greater improvement in muscle strength, stability of gait, and fewer falls was found in elderly women under calcium and vitamin D supplementation/day (Bischoff-Ferrari et al. 2004). The most active metabolite of vitamin D, calcitriol, has been used in osteoporosis, because it stimulates bone and may normalize calcium absorption and calcium balance. Clinical trials with calcitriol for the treatment of osteoporosis showed conflicting results, whereby it frequently caused hypercalcemia or hypercalciuria necessitating close monitoring. So, present recommendations for vitamin D supplementation suggest a daily vitamin D intake of at least 700–800 IU plus 1200 mg calcium/day in the diet or as a supplement [NIH].

] Estrogen replacement For a long time estrogen replacement therapy (ERT) was considered to be a primary intervention for the prevention of postmenopausal os-

21 Evidence-based drug treatment of osteoporosis

teoporosis, but recurrence of menstrual-like bleeding and premenopausal symptoms was not readily accepted by many women. There also seemed a possible connection between estrogen replacement and cancer of the breast and uterus. The threat of endometrial malignancy was reduced by applying combined estrogenprogestin therapy. This combined treatment reduces the risk for vertebral and extravertebral fractures, including hip fractures. Because of possible deleterious effects, however, especially in older drug prescriptions estrogen-progestin treatment is no longer accepted as a first-line approach for the treatment of osteoporosis in postmenopausal women. But possible indications include persistent menopausal symptoms with the need for antiresorptive treatment if other drugs cannot be tolerated.

] Selective estrogen receptor modulators (SERMs) Tamoxifene, the first available SERM, is an estrogen antagonist that binds to the estrogen receptor. It has a bone sparing effect at the usual dosage of 20 mg/day. It is useful in the treatment of menopausal women who suffer from cancer of the breast. Tamoxifene decreases the risk of fractures of the hip and spine, but not of the distal radius. Therapy should be limited to 5 years, because tamoxifene stimulates endometrial tissue and may increase the incidence of endometrial carcinoma. Raloxifene is a tissue selective estrogen receptor modulator for the prevention and treatment of osteoporosis with estrogen agonistic response by TGF-b stimulation only at the site of the bone. It harmonizes bone turnover physiologically by natural pathways thus increasing bone mineral density and decreasing the incidence of vertebral fractures. Adverse effects are the reduction of serum total and LDL cholesterol concentrations, and it does not stimulate endometrial hyperplasia or vaginal bleeding. Therefore, raloxifene is recommended as one of the first line drugs for prevention of osteoporosis, but it seems less effective than estrogen and bisphosphonates, considering that the increase of bone mineral density is a factor which is more and more discussed as a relevant outcome parameter.

]

] Calcitonin in the prevention and treatment of osteoporosis Calcitonin, a peptide composed of 32 amino acids, binds to osteoclasts and inhibits bone resorption. Calcitonins from many species are effective in humans. Salmon calcitonin is most widely used. It is highly potent in humans and has a high affinity for the human calcitonin receptor with a slow rate of clearance. The only other calcitonin used clinically is the human preparation which is less potent but also less antigenic. The route of application can be subcutaneous, intramuscular, and nasal, whereby the biological effect of 50 IU of intramuscular salmon calcitonin is equal to that of 200 IU of the nasal preparation. Studies of the efficacy of calcitonin together with calcium supplementation over two years to prevent postmenopausal bone loss showed a significant increase of mean spinal bone mineral density. But conflicting data exist – in favour of calcitonin – at sites other than the spine. Calcitonin is less effective than bisphosphonates for the treatment of postmenopausal osteoporosis. Combined with estrogen, calcitonin seems to have a synergistic effect, and it is also accepted for the treatment of glucocorticoid-induced osteoporosis (Ringe and Welzel 1987). Calcitonin is not used as a first-line treatment for osteoporosis. Its traded clinical indication is the treatment for prominent pain (especially back pain) and it can decrease the risk for vertebral bone fractures. Its beneficial shortterm effect on pain in patients with fractures is probably due to the rise in endorphin levels. However, its bad adherence when subcutaneously applied, its side effects (i.e., vomiting and flush) and the price level for the nasal application form result in a lower use. The development of antibodies often signals resistance too. The rise of alkaline phosphatase in patients with Paget’s disease signals that the patient becomes resistant to calcitonin. Such a warning system is lacking in osteoporosis, because calcitonin has only a minimal effect on biochemical markers of bone turnover.

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] The use of bisphosphonates in osteoporosis Chemically, bisphosphonates are synthetic analogues of inorganic pyrophosphate, which have a high affinity for calcium. They clear rapidly from the circulation, bind to bone lining surfaces and concentrate selectively in bone. If not incorporated into the bone’s mineral matrix, bisphosphonates underly renal elimination. They have been used in patients with various disorders affecting the skeleton, including individuals with hypercalcemia, Paget’s disease, multiple myeloma, metastases of breast cancer, and osteogenesis imperfecta. These drugs inhibit bone resorption and reduce the incidence of vertebral and nonvertebral fractures even in women who already had fractures. Furthermore, they are beneficial in the treatment of glucocorticoid-induced osteoporosis. The first bisphosphonate used to treat osteoporosis was etidronate (editronate). Because of concern that it may cause osteomalacia, however, it was superseeded by other bisphosphonates. Table 21.5 lists the potency of the various bisphosphonates used in humans, Table 21.6 shows the bisphosphonates registered in Germany. In women with postmenopausal osteoporosis 10 mg alendronate a day for three years showed significant increases in bone mineral density of the spine, hip and total skeleton. A decrease of new vertebral fractures was also noted (Lieberman et al. 1995). Several trials proved the longterm efficiency of alendronate up to 12 years in women with osteoporosis. Table 21.5. Potency of various bisphosphonates used in humans to inhibit bone resorption (Watts 1998) Generation

Bisphosphonate

] First generation

Etidronate (Editronate) Clodronate

] Second generation ] Third generation

Tiludronate Pamidronate Alendronate Risedronate (Residronate) Ibandronate Zolendronate

Postmenopausal women with osteoporosis were randomly assigned to be treated with placebo or different doses of alendronate. All women also received 500 mg calcium per day (Lieberman et al. 1995). At three years of treatment bone density slightly decreased in the placebo group but increased in the alendronate group at the mid-forearm, femoral neck, and spine. Alendronate was associated with fewer vertebral fractures, less loss of height, and at a dose of 10 mg a day had no increase in side effects as compared to placebo. In another trial over 3 years in postmenopausal women alendronate was associated with a lower incidence of vertebral fractures, and with a lower rate of clinical fractures of hip and wrist. Alendronate (5 mg per day for 2 years followed by 10 mg a day for 2 years) was tested in postmenopausal women with low bone density but no history of osteoporotic fractures. In elderly women alendronate increased bone mineral density at all sites, prevented osteoporosis and reduced the number of clinical fractures (Greenspan et al. 2000).

Table 21.6. Selected bisphosphonates used in Germany for the treatment of osteoporosis Bisphosphonate

Drug names

] Etidronate (Editronate)

Editron HEXAL 200/400 mg tbl., Didronel 200 mg tbl. Editronat-Jenapharm 200 mg tbl., 400 mg a day

] Alendronate

Fosamax, tbl., 10 mg/day and 70 mg/ week, Fosavance (combination with Vit. D) Alendronsäure AWD, Alendron-Hexal, tbl., 70 mg/week each Alendronsäure STADA, tbl., 10 mg/day, 70 mg/week

] Risedronate (Residronate)

Actonel 5 mg tbl./day, 35 mg once a week Combination “Actonel plus Calcium D”

] Ibandronate

Bonviva 3 mg/3 ml prefilled syringe i.v. every 3 month, 100 tbl. 150 mg per month

Antiresorptive potency 1 10 10 100 100–1000 1000–10 000 1000–10 000 > 10 000

Aclasta 5 mg, given as an intravenous ] Zoledronate (Zoledronic acid) infusion in a 100 ml solution, applied once a year

21 Evidence-based drug treatment of osteoporosis

In a study over three years alendronate increased bone mineral density at the lumbar spine, femoral neck, trochanter, and total hip (McClung et al. 1998). The positive effects of alendronate disappeared rapidly after cessation of therapy. Similar results were reported in another study when 5 mg of alendronate a day were given for 2 years to postmenopausal women under the age of sixty. A four and six year follow-up demonstrated that the positive effects of continued therapy on bone density were maintained (McClung et al. 2004). The combination of drugs, bisphosphonates or estrogens, inhibit bone resorption by different mechanisms and also has additive effects on bone mineral density. This was confirmed with etidronate (editronate) and alendronate (Bone et al. 2000). The combination of alendronate and a SERM (raloxifene) also showed additive effects on bone mineral density (Johnell et al. 2002). Application of 70 mg alendronate once a week was found to be similar in efficacy than 10 mg once a day. There were fewer side effects with the once-a-week dosis. A comparison (with fracture end points) between alendronate and the other weekly dosed 35 mg of residronate does not exist. It seems that the suppressive rate of resorption of alendronate is higher but the onset of clinical fracture resorption slightly slower (Rosen et al. 2005). Alendronate has been found to be well tolerated and effective for at least 10 years. In women with postmenopausal osteoporosis it increases bone mineral density over a ten-year period (Bone et al. 2004). The Fracture Intervention Trial showed similar results after 6 to 10 years of follow-up (Ensrud et al. 2004). To minimize the risk of esophageal disease in patients treated with alendronate, the following rules should be applied: The drug should not be given to patients with active upper gastrointestinal disease, it should be discontinued in patients with symptoms of esophagitis, when creatinine clearance is below 35 mg/h and in presence of signs of osteoarthritis of the jaw. Alendronate should be taken on an empty stomach in the morning 1 h before eating with a full glass of plain water while sitting or standing. The patient should remain upright for at least 1/2 h before any food intake. Risedronate (Residronate), another clinically very important bisphosphonate, increased bone density at the lumbar spine, femoral neck, tro-

]

chanter, and hip (Sorensen et al. 2003). It was the first published bisphosphonate that specifically decreased the incidence of hip and not only of extravertebral fractures (McClung et al. 2001). Furthermore, in patients treated with glucocorticoids, risedronate could significantly prevent more bone loss (Cohen et al. 1999). The efficacy of risedronate seems to be quite similar to that of alendronate, however, alendronate may have a greater effect on bone mineral density at all sites after 12 months of treatment (Rosen et al. 2005). Greater decreases in biochemical markers of resorption were noted with alendronate by 3 months, a possible effect of its higher bone affinity and fixation. There was a tendency to slightly higher adverse effects in the upper gastrointestinal tract with alendronate treatment in comparison with risedronate. Combination therapy of conjugated estrogens with risedronate showed a greater increase of bone density at the femoral neck and the radial bone as when given alone (Harris et al. 2001). Three risedronate formulations are used: A once a day 30 mg dose for the treatment of Paget’s disease, a 5 mg daily and a 35 mg weekly dosis for the treatment and the prevention of postmenopausal and glucocorticoid-induced osteoporosis. Ibandronate is a newer bisphosphonate for the prevention and treatment of osteoporosis. In a 3 year evaluation bone mineral density increased. Both daily and intermittent treatment with ibandronate decreased the risk of only vertebral but not of hip fractures. A decrease in nonvertebral fractures was seen only with daily ibandronate treatment in patients with a BMD T-score less than –3.0 (Chesnut et al. 2004). The dosage regimens contain especially a once-amonth tablet with 150 mg and an injectable formulation with 3 mg/3 ml. Zoledronic acid, the latest potent drug of the bisphosphonate family, is the only bisphosphonate that is administered once a year. The drug is given as an intravenous infusion of 5 mg zoledronic acid in a 100 ml solution. The onceyearly administration is made possible by 100% bioavailability, a high affinity to bone and a strong inhibition of osteoclasts. Zoledronic acid is available in many countries for the treatment of postmenopausal osteoporosis, including the approval in 2007 in the US, Canada and the EU. In the HORIZON Pivotal Fracture Trial (PFT) zoledronic acid reduced the risk for new verte-

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bral fractures by 70% compared with placebo over three years (Black et al. 2007). In addition the risk for hip fractures and non-vertebral fractures was reduced significantly by 41% and 25%, respectively. Thus, zoledronic acid is the only osteoporosis treatment that has been shown to reduce the risk for fractures at all relevant osteoporotic sites. It should be recognized that the HORIZON PFT is the first study that allowed the patients the use of concomitant osteoporosis medication. Zoledronic acid increased bone mineral density at the lumbar spine, total hip and femoral neck. Bone markers were reduced and maintained in the premenopausal reference range. In addition, the drug was shown to reduce the number of days with disability and bed rest caused by back pain or fractures. The use of zoledronic acid was associated with a higher incidence of flu-like symptoms that occurred within three days after infusion and resolved quickly. In a recent study (HORIZON Recurrent Fracture Trial) the efficacy of zoledronic acid in the prevention of clinical fractures and the reduction of mortality in men and women with hip fracture was investigated (Lyles et al. 2007). Patients were randomized within 90 days after surgical repair of a hip fracture and received an annual infusion of zoledronic acid or placebo. The mean follow-up time was 1.9 years. Zoledronic acid was shown to reduce clinical fractures after hip fracture by 35%. In addition, allcause mortality was reduced by 28% in the zoledronic acid treated patients. This is the first time that an osteoporosis medication was shown to reduce clinical fractures and mortality in patients after hip fracture. In summary, the once yearly infusion of zoledronic acid is a highly effective and safe treatment for postmenopausal osteoporosis that offers additional advantages concerning the compliance of the patients. Further specific bisphosphonate formulations and drugs for the treatment of Paget’s disease are tiludronate, risedronate, and zoledronate.

] Adverse effects of bisphosphonates Alendronate may induce esophagitis and esophageal ulcers. Esophageal strictures and gastric ulcers can occur (Graham and Malaty 1997). Concomitant use of nonsteroidal anti-inflammatory drugs may increase the occurrence of gastric ulcers (Graham and Malaty 2001). The risk

of esophageal side effects seems lower with risedronate, even in patients with a history of esophageal disease. Treatment with an oral bisphosphonate lowers serum calcium, but clinically significant hypocalcemia has been reported only in hyperparathyroidism (Schussheim et al. 1999). Ocular side effects (including pain, blurred vision, conjunctivitis, uveitis, scleritis) have rarely been seen (Frauenfelder and Frauenfelder 2000). Occasionally patients have experienced musculoskeletal pain while taking bisphosphonates.

] Parathyroid hormone and teriparatide Teriparatide is the recombinant 1–34 truncated human parathyroid hormone (PTH). Its anabolic effects on bone formation have been originally studied in postmenopausal women and in men with advanced osteoporosis, which was the indication and formulation for approval in the United States. Teriparatide is available throughout most of the world, but recombinant fulllength PTH (1–84) is the second now available rh-PTH in Europe. In many countries in Europe, teriparatide or PTH (1–84) cannot be administered unless a patient has received a previous, unsuccessful course of bisphosphonate therapy for at least 1 year and has had further osteoporotic fracture or a severe course of osteoporosis with at least two or more vertebral fractures. These restrictive indications are due, in part, to the fact that teriparatide is expensive and is administered by daily subcutaneous injection. Adverse events with teriparatide include mild hypercalcemia, other side effects are rise in serum uric acid, dizziness, headache, nausea, and leg cramps (Canalis et al. 2007).

] Strontium ranelate Strontium ranelate, like calcium, becomes incorporated around the crystal structure of bone. Both, its anabolic and antiresorptive actions have been reported, particularly in in vivo models. Bone biopsy specimens from patients treated with strontium ranelate show a reduction in bone resorption but possibly no evidence of increased bone formation (Canalis et al. 2007). The rationale of its use is its agonism on the CaSR (calcium sensing receptor) and its

21 Evidence-based drug treatment of osteoporosis

anabolic effect on osteoblasts via osteoprotegerin, as well as its effect on the osteoclasts by reduced metabolism and replication rate without apoptosis. Strontium ranelate is approved in Europe, but is not approved in the United States for the treatment of postmenopausal osteoporosis. It is administered orally (powder solution, 2 mg/day) and has only few side effects.

Other treatments for osteoporosis ] Fluoride therapy in osteoporosis From animal studies it is known that fluoride stimulates bone formation by osteoblasts. Based on the early observation of one of the adverse effects of fluoride intoxication (“fluorosis”), the first clinical studies found that the administration of fluoride greatly increased bone density of the spine. The subsequent use of fluoride was limited, however, for its side effects (gastrointestinal symptoms, lower extremity pain). In addition, fluoride treatment may cause an osteomalacia-like bone effect and loss of cortical bone as it increases trabecular bone. Another disadvantage is that fluoride-containing bone is structurally weaker than normal bone. Mainly during the last decade of the last century research led to more safe fluoride formulations (slow-release sodium fluoride; monosodiumfluorophosphate) and to more clinical research. Women with moderate osteoporosis, for instance, were treated with low doses of sodium monofluorophosphate (20 mg/day fluoride) plus 1000 mg calcium carbonate/day for 4 years. In this trial, evaluated by the pharmaceutical sponsor itself, the fluoride preparation – compared to only calcium carbonate treatment – did not influence the occurrence of nonvertebral fractures. Concerning vertebral fractures, however, the fluoride group was said to show a lower incidence of new fractures compared to the group receiving calcium alone (Reginster et al. 1998). In contrast, another trial of higher doses of monosodium fluoride and enteric-coated sodium fluoride found no decrease in the incidence of vertebral fractures (Meunier et al. 1998). Because of conflicting data, after 40 years research on the treatment of osteoporosis with

]

fluoride, the NIH “Consensus Development Panel on Osteoporosis Prevention, Diagnosis, and Therapy“ (2001) did not come to a clear conclusion that fluoride is effective in osteoporosis. Today, this is reflected more and more by national (e.g. O’Neill et al. 2004) and especially international scientific societies (e.g. Kanis et al. 2008) which have eliminated fluoride from their recommendations of treatments for the prevention of fractures. Fluoride should generally be reserved only for patients with vertebral fractures who definitively are unable to tolerate any other approved drug for the treatment of osteoporosis.

] Thiazide and loop diuretics Concomitant administration of diuretics can influence calcium balance. Loop diuretics increase calcium excretion by impairing reabsorption in the loop of Henle. The ensuing negative calcium balance, therefore, can enhance the risk for hip fractures. Thiazides stimulate distal tubular reabsorption of calcium. They decrease the urinary calcium excretion. This effect leads to a reduced frequency of stone formation in patients with nephrolithiasis and hypercalciuria. Most studies have demonstrated a beneficial effect on fracture risk. In a meta-analysis of 13 trials the hip fracture risk was significantly reduced by 18% with long-term thiazide therapy (Jones et al. 1995). From the data published it can be concluded that thiazides attenuate bone loss and may reduce fracture risk, but the effect is moderate. Therefore, thiazides are not routinely recommended for the prevention or treatment of osteoporosis, but they may have a place in the treatment of patients with osteoporosis who have hypertension or nephrolithiasis. The effects of diuretics on optimal dietary calcium intake is not known.

] Alternative medicine/phytoestrogens Data from animal studies suggests a positive effect of phytoestrogens on bone, but valid clinical studies – especially long-term trials – are lacking.

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] New treatments on the horizon Besides the variety of the therapeutic options of today, new forms of treatment are appearing like cathepsin K inhibitors or RANK/RANK-ligand inhibitors. Potent and selective inhibitors have been designed for cathepsin K, a cysteine protease unique to osteoclasts. They have demonstrated antiresorptive activity both in vitro and in vivo and therefore they are promising new agents for the treatment of osteoporosis. Research concerning interactions of osteoclastogenesis, bone resorption and remodeling may offer new therapeutic potential. RANK(receptor activator of nuclear factor NF-jB-) ligand is the key activator for bone resorption. Osteoprotegerin (OPG) and also the human monoclonal antibody denosumab both inhibit the binding of RANK-ligand to RANK and thus prevent bone resorption.

Evidence-based conclusion Osteoporosis affects millions of mainly postmenopausal women all over the world, especially in developed countries. In Germany, half of all women at the age of 50 years or more have suffered from at least one osteoporotic fracture. These are the patients who bear the five-fold risk to develop a new fracture within the following year. This means a new responsibility for the (hip) surgeon: the management of established osteoporosis (Bartl 2003). The basis of this (acute) management is a careful case history and diagnosis of the (osteoporotic) fracture, particularly with help of dualenergy X-ray absorptiometry (DXA), the immediate start of an anti-osteoporosis (drug) therapy and thus the effective reduction of the risk of further fractures (Bartl 2003) Although potentially devastating, in general, osteoporotic fractures can be prevented, their incidence at least reduced. Change of life-style in the sense of regular weight-bearing exercise, avoidance of smoking and excessive alcohol and caffeine consumption, diet with adequate calcium and vitamin D intake are able to protect against mineralization loss and deterioration of bone quality.

Pharmacological intervention is also able to increase bone density and thus reduces the fracture risk in women (and men) with established osteoporosis. Today, besides calcium and vitamin D, ERT starting within 5 years of menopause, raloxifene, bisphosphonates (alendronate, risedronate, ibandronate, zoledronate), strontium ranelate, PTH, and partly calcitonin (nasal application) are good general pharmacological strategies to avoid – or at least reduce – the loss of bone mineralization density and thus vertebral and extravertebral fractures in osteoporotic patients. Concerning especially the reduction of hip fractures, alendronate, risedronate, zoledronate, and strontium ranelate show the best evidence, based on extensive clinical experience. Summarizing, good evidence suggests that many agents are effective in preventing osteoporotic fractures, but up to now, only few studies have directly compared different agents or classes of agents used to treat osteoporosis (MacLean et al. 2008). Research of the near future has to determine their relative efficacy and safety. ] Acknowledgements. This contribution is warmly dedicated to Prof. Dr. med. Gerhard L. Bach (MD, former Professor and Chairman, University of Illinois, Cook County Postgraduate School of Medicine, Chicago, USA), D-67269 Grünstadt, at the occasion of his 74th birthday. The authors are much obliged to Dr. med. Thomas Drabiniok (Fachkliniken Hohenurach), D-72574 Bad Urach, for constructive discussions as well as to Andrea Förster, D-12047 Berlin, for the careful review of the manuscript.

References Bartl R (2003) Management der manifesten Osteoporose – eine neue Verantwortung für den Unfallchirurgen (Editorial). Unfallchirurg 106:525 Bartl R, Bartl C (2004) Osteoporose-Manual. Diagnostik, Prävention und Therapie. Springer, Berlin Heidelberg New York Bischoff-Ferrari HA, Dietrich T, Orar EJ et al (2004) Positive association between 25-hydroxy vitamin D levels and bone mineral density: A population based study of younger and older adults. Am J Med 116:634 Bischoff-Ferrari HA, Willett WC, Wong JB et al (2005) Fracture prevention with vitamin D supple-

21 Evidence-based drug treatment of osteoporosis mentation: A meta-analysis of randomized controlled trials. JAMA 293:2257 Black DM, Delmas PD, Eastell R et al (2007) Onceyearly zoledronic acid for treatment of postmenopausal osteoporosis. N Engl J Med 356:1809–1822 Bone HG, Greenspan SL, McKeever C et al (2000) Alendronate and estrogen effects in postmenopausal women with low bone mineral density. Alendronate/Estrogen Study Group. J Clin Endocrinol Metab 85:727 Bone HG, Hosking D, Devogelaer JP et al (2004) Ten years’ experience with alendronate for osteoporosis in postmenopausal women. N Engl J Med 350:1189 Canalis E, Giustina A, Bilezikian JP (2007) Mechanisms of anabolic therapies for osteoporosis. N Engl J Med 357:905–916 Chapuy MG, Arlot ME, Duboef F (1992) Vitamin D3 and calcium to prevent hip fractures in elderly women. N Engl J Med 327:1637–1642 Chesnut CH 3rd, Skag A, Christiansen C et al (2004) Effects of oral ibandronate administered daily or intermittently on fracture risk in postmenopausal osteoporosis. J Bone Miner Res 19:1241 Cohen S, Levy RM, Keller M et al (1999) Risedronate therapy prevents corticosteroid-induced bone loss: A twelve-month, multicenter, randomized, doubleblind, placebo controlled, parallel-group study. Arthritis Rheum 42:2309 Cummings SR, Black DM, Thompson DE et al (1998) Effect of alendronate on risk of fracture in women with low bone density but without vertebral fractures. Results from the Fracture Intervention Trial. JAMA 280:2077 DVO-Leitlinie 2006 zur Prophylaxe, Diagnostik und Therapie der Osteoporose bei Frauen ab der Menopause und bei Männern ab dem 60. Lebensjahr. Osteol 15:198 Eastell R, Baumann M, Hoyle NR, Wieczorek L (eds) (2001) Bone markers: biochemical and clinical perspectives. Martin Dunitz Ltd, London Ensrud KE, Barrett-Connor EL, Schwartz A et al (2004) Randomized trial of effect of alendronate continuation versus discontinuation in women with low BMD: Results from the Fracture Interaction Trial long-term extension. J Bone Miner Res 19:1259 Frauenfelder FW, Frauenfelder FT (2003) Bisphosphonates and ocular inflammation. N Engl J Med 348:1187 Fulton JP (1999) New guidelines for the prevention and treatment of osteoporosis. National Osteoporosis Foundation. Med Health RI 82:110 Graham DY, Malaty HM, Goodgame R (1997) Primary amino-bisphosphonates: A new class of gastrotoxic drugs comparison of alendronate and aspirin. Am J Gastroenterol 92:1322 Graham DY, Malaty HM (2001) Alendronate and Naproxen are synergistic for development of gastric ulcers. Arch Intern Med 161:107

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Harris ST, Eriksen EF, Davidson M et al (2001) Effect of combined risedronate and hormone replacement therapies on bone mineral density in postmenopausal women. J Clin Endocrinol Metab 86:1890 Harris ST, Watts NB, Jackson RD et al (1993) Fouryear study of intermittent cyclic etidronate treatment of postmenopausal osteoporosis: three years of blinded therapy followed by one year of open therapy. Am J Med 95:557 Johnell O, Scheele WH, Lu Y et al (2002) Additive effects of raloxifene and alendronate on bone density and biochemical markers of bone remodeling in postmenopausal women with osteoporosis. J Clin Endocrinol Metab 87:985 Jones G, Nguyen T, Sambrook PN, Eisman JA (1995) Thiazide diuretics and fractures: Can meta-analysis help? J Bone Miner Res 10:106–111 Kanis JA, Burlet N, Cooper C et al (2008) European guidance for the diagnosis and management of osteoporosis in postmenopausal women. Osteoporos Int 19:399–428 Keck E, Kruse HP (1994) Osteoporose. Klinik, Diagnostik, Therapie. Fischer, Jena Stuttgart LaCroix AZ, Ott SM, Ichikawa L et al (2000) Low-dose hydrochlorothiazide and preservation of bone mineral density in older adults: A randomized, double-blind, placebo-controlled clinical trial. Ann Intern Med 133:516 Lane N, Leboff MS (2005) Metabolic Bone Disease. In: Harris ED, Budd RC, Firestein GS et al (eds) Kelley’s Textbook of Rheumatology, Vol. II, 7th ed. Elsevier-Saunders, Philadelphia, pp 1473–1492 Lieberman UA, Weiss SR, Bröll HJ et al (1995) Effect of oral alendronate on bone mineral density and the incidence of fractures in postmenopausal women. N Engl J Med 333:1437–1443 Lindsay R, Marcus R, Recker R (1996) Osteoporosis: What’s new in prevention and treatment. Patient Care 30:24–28, 30–31, 35–36 Lyles KW, Colón-Emeric CS, Magaziner JS et al (2007) Zoledronic acid and clinical fractures and mortality after hip fracture. N Engl J Med 357: 1799–1810 MacLean C, Newbery S, Maglione M et al (2008) Systematic Review: Comparative Effectiveness of Treatments to Prevent Fractures in Men and Women with Low Bone Density in Osteoporosis. Ann Intern Med 148:197–213 McClung M, Clemmesen B, Daifotis A et al (1998) Alendronate prevents postmenopausal bone loss in women without osteoporosis: A double-blind, randomized, controlled trial. Ann Intern Med 128:253 McClung MR, Geusens P, Miller PD et al (2001) Effect of risedronate on the risk of hip fracture in elderly women. N Engl J Med 344:333 McClung MR, Wasnich RD, Hosking DJ et al (2004) Prevention of postmenopausal bone loss: Six-years results from the Early Postmenopausal Interven-

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tion Cohort Study. J Clin Endocrinol Metab 89: 4879 Meunier PJ, Sebert JL, Reginster JY et al (1998) Fluoride salts are no better at preventing new vertebral fractures than calcium-vitamin D in postmenopausal osteoporosis. Osteoporosis Int 8:4 NIH (1994) Consensus Development Panel on Optimal Calcium intake. JAMA 272:1942–1948 NIH Consensus Development Panel on Osteoporosis Prevention, Diagnosis, and Therapy (2001) Osteoporosis prevention, diagnosis, and therapy. JAMA 285:784–795 National Osteoporosis Foundation (2003) Physician’s guide to prevention and treatment of osteoporosis. Washington, DC Nordin BEC (1997) Calcium and osteoporosis. Nutrition 13:664–686 O’Neill S, MacLennan A, Bass S, et al. (2004) Guidelines for the management of postmenopausal osteoporosis for GPs. Aust Fam Physician 33:910–919 Peters KM (2005) Evidenz-basierte medikamentöse Behandlung der Osteoporose In: Heisel J, Drabiniok T (Hrsg) Osteoporose-Update. Med.-Lit. Verlagsges, Uelzen, S 24–30 Reginster JY, Meurmans L, Zegels B et al (1998) The effect of sodium monofluorophosphate plus calcium on vertebral fracture rate in postmenopausal

women with moderate osteoporosis. A randomized, controlled trial. Ann Intern Med 129:1 Reid IR, Brown JP, Burckardt P et al (2002) Intravenous zoledronic acid in postmenopausal women with low bone mineral density. N Engl J Med 346:653 Ringe JD, Welzel D (1987) Salmon-calcitonin in the therapy of corticoid-induced osteoporosis. Eur J Clin Pharmacol 33:35–39 Rosen CJ, Hochberg MC, Bonnick SL et al (2005) Treatment with once-weekly alendronate 70 mg compared with once-weekly residronate 35 mg in women with postmenopausal osteoporosis: A randomized double-blind study. J Bone Miner Res 20:141 Sambrook P, Cooper C (2006) Osteoporosis. Lancet 367:2010–2018 Sambrook PN, Kelly PJ, Morrison NA et al (1994) Scientific review: Genetics of osteoporosis. Br J Rheumatol 33:1007–1011 Schussheim DH, Jacobs TP, Silverberg SJ (1999) Hypocalcemia associated with alendronate (letter). Ann Intern Med 130:329 Sorensen OH, Crawford GM, Mulder H et al (2003) Long-term efficacy of risedronate: A 5-year placebo-controlled clinical experiment. Bone 32:120 Wüster C (1995) Prävention und Therapie der Osteoporose. Münch Med Wschr (MMW) 137:846–853

Closing remarks K.-K. Dittel

plant with exact adaption to any individual anatomical situation of the patient can be described as the – “gold nugget” – under the implants in the group of extramedullary orientated devices. The universality of the DMS is based on the double dynamic kind of stabilization using the sliding link principle and the angle stable adaptability simultaneously. There will be absolutely no doubt that the implant whose operative indications have been reported in this book will also succeed in the future for the benefit of a great number of our patients which have to be treated because of fractures at the proximal and distal end of the femur.

Fig. 22.1

Since the first implantation of a Dynamic Martin Screw (DMS) on the 15th of November 1992 (70 years old female with a combined inter- and subtrochanteric femur fracture) the implant has started its worldwide success. Meanwhile more than 50 000 patients have been treated with the adjustable femur plate because of operative fracture indications. The increasing spreading was accompanied by antipathy and envy, but these collateral side effects could not disturb the spreading of an idea which had been realised at the right time. The technical optimised implant is unique in its use especially when a severe osteoporosis is combined with an acute fracture situation. The implant guarantees a perfect congruence between the plate and the lateral cortical surface by its anatomical adjustment. The universal applicability of the extramedullary orientated im-

Fig. 22.2

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Ateschrang A (2000) Die Prognose der medialen Schenkelhalsfraktur bei kopferhaltender Osteosynthese. Inauguraldissertation Universität Tübingen Ateschrang A, Dittel KK (2007) The Dynamic Martin Screw: an alternative for intracapsular femoral neck fractures? Eur J Trauma Emerg Surg 33:635–640 Babst R et al (1993) Die DHS-Abstützplatte für die Versorgung der instabilen proximalen Femurfrakturen. Schweiz med Wschr 123:566–568 Baumgart R, Betz A, Kessler S, Kettler M, Schweiberger L (2004) Möglichkeiten der Rekonstruktion von Knochendefekten. Orthopädie 23:396–403 Binder EF, Brown M, Sinacore DR, Steger-May K, Yarasheski KE, Schechtman KB (2004) Effects of extended outpatient rehabilitation after hip fracture: a randomized controlled trial. JAMA 292:837–846 Bonnaire F, Götschin U, Kuner EH (1992) Früh- und Spätergebnisse nach 200 DHS-Osteosynthesen zur Versorgung pertrochantärer Femurfrakturen. Unfallchirurg 95:246–253 Bonnaire F, Hellmund R, Lein T (2003) DHS – Stärken und Schwächen der Platten-Schrauben-Kombination. Trauma Berufskrankh 5(Suppl 2):162–170 Brien WW, Wiss DA, Becker V Jr, Lehmann T (1991) Subtrochanteric femur fractures: a comparison of the zickel nail, 958 blade plate, and interlocking nail. J Orthop Trauma 5:458 Brüggemann H (1982) Die Verbundosteosynthese – experimentelle Grundlagen. Thieme, Stuttgart, S 34–38 Butt MS, Krikler SJ, Nafie S, Ali MS (1995) Comparison of dynamic hip screw and gamma nail: a prospective, randomized, controlled trial. Injury 26:615 Chaim SH et al (2002) A biomechanical study of femoral neck fracture fixation with the VHS VariAngle Hip Fixation System. Am J Orthop (Suppl), pp 22–24 Chiari K (1956) Ergebnisse mit der Beckenosteotomie als Pfannendachplastik. Z Orthop 87:14 Curtis MJ, Jinnah RH, Wilson V, Cunningham W (1994) Proximal femoral fractures: a biomechanical study to compare intramedullary and extramedullary fixation. Injury 25:99 Dittel KK (1993) Die Osteosynthese pertrochantärer Oberschenkelfrakturen mit einer neuen winkeladaptierbaren dynamischen Gleitlasche. 57. Jahres-

tagung der Deutschen Gesellschaft für Unfallchirurgie eV, Berlin. Abstract-Band, S 66 Dittel KK (1994) An innovative method for stabilization of proximal femur fractures. Abstract-Book. Br J Surg 81 (Suppl 1):126 Dittel KK (1994) Dynamische Osteosynthese pertrochantärer Oberschenkelfrakturen mit einer winkeladaptierten Laschenplatte. Kongressband Osteosynthese International Erlangen 1993. Druckhaus Mayer, Erlangen, S 95–102 Dittel KK (1995) Ein innovatives Stabilisierungsverfahren für proximale Femurfrakturen. Osteosynthese International (Kongressband), Leuven University Press, S 193–198 Dittel KK, Felenda MR (1998) Operative Behandlung der Gelenk- und Schaftfrakturen. Thieme, Stuttgart New York Dittel KK, Felenda MR (1998) Spezielle Indikationsstellung zur Osteosynthese supracondylärer Femurfrakturen mit der DMS. In: Rahmanzadeh, Voigt, Trabhardt (Hrsg) Wiederherstellungschirurgie des Kniegelenkes – Wandel in der Osteosynthesetechnik. Eichhorn, S 148–153 Dittel KK, Felenda MR (1999) Erste klinische Erfahrungen mit einer zementfreien extrametaphysär orientierten Schenkelhalsprothese. Osteosynthese International 7(Suppl 2):164–167 Dittel KK, Rapp M (1995) Ein neues Prinzip zur Stabilisierung proximaler Femurfrakturen. Osteosynthese International 1:46–54 Dittel KK, Rapp M (2004) 10 years of experience with the DMS (Dynamic Martin Screw) in the treatment of proximal and distal femoral fractures. Osteosynthese International Kongress 2004, Graz/Österreich, Abstract-Band 41 Dittel KK, Rapp M (2005) Winkelstabile Implantate am proximalen Femur. Akt Traumatol 35:155–162 Dittel KK, Reinecke M (1998) Erste klinische Erfahrungen mit einer zementfreien extrametaphysär orientierten Schenkelhalsprothese. Hefte zu Der Unfallchirurg. Springer, S 718–719 Dittel KK, Weise K (2003) Komplikationsmanagement in der Traumatologie. Thieme, Stuttgart New York Dittel KK, Kraft E, Metzger H (1988) Die Femurinstabilität als Komplikation des ossär metastasierenden Mammakarzinoms. Chir Praxis 39:73–89

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Heinz T, Vecsei V (1994) Komplikationen und Fehler bei der Anwendung des Gammanagels. Ursachen und Prävention. Chirurg 65:943–952 Hoffmann R, Schmidmaier G, Schulz R, Schütz M, Südkamp NP (1999) Classic-Nail vs. dynamische Hüftschraube (DHS): Eine prospektiv-randomisierte Studie zur Behandlung pertrochantärer Femurfrakturen. Unfallchirurg 102:182–190 Holz U (1985) Verbundosteosynthese bei Spontanfrakturen am Femur. Akt Traumatol 15:100–103 Josten Ch, Tiemann AH (2002) Komplikationen nach proximalen Femurfrakturen. OP-Journal 17:148– 153 Kinast C, Bolhofner BR, Mast JW, Ganz R (1989) Subtrochanteric fractures of the femur. Results of treatment with the 958 condylar blade-plate. Clin Orthop 138:122 Kostuj T, Luka M, Smektala R (2000) Subtrochantäre Femurfrakturen – Osteosynthese mit DHS und Trochanterabstützplatte: Ergebnisse der Jahre 1996–2000. Akt Traumatol 30:168–172 Krause D, Phillip J, Lucke C (1996) Operative Ergebnisse subtrochantärer Femurfrakturen – Eine Studie über 15 Jahre. Unfallchirurg 99:196–201 Legal H (1985) Osteotomien an der Dysplasiehüfte des Erwachsenen – Planung unter Berücksichtigung einer differenzierten biomechanischen Berechnung. Z Orthop 123:465 Marti RK, Dunki Jacobs PB (1993) Proximal femoral fractures, vol 1. Medical Press LTD, London Marti RK, Dunki Jacobs PB (1993) Proximal femoral fractures, vol 2. Medical Press LTD, London Meißner A, Rahmanzadeh A (1989) Entwicklungen in der Behandlung von Frakturen des coxalen Femurendes. Akt Traumatol 19:262–273 Molinar Min AM, Moselli M (1995) La vite-placca DMS nell’ osteosintesi delle fratture pertrocanteriche die femore. Minerva Ortop Traumatol 46: 329–330 Muhr G (1984) Formen und Technik der hüftgelenksnahen Femurosteotomie. In: Hierholzer G, Müller KH (Hrsg) Korrekturosteotomien nach Traumen an der unteren Extremität. Springer, Berlin, S 77 Müller ME (1979) Planung einer komplexen intertrochanteren Osteotomie. Z Orthop 117:145 Müller ME, Nazarin S, Koch P (1987) Classification AO des fractures. Springer, Berlin Heidelberg New York Niethard FU, Pfeil J (1989) Hüftgelenk und Oberschenkel. In: Orthopädie. Hippokrates, Stuttgart, S 405 Ostermann PAW, Haase N, Ekkernkamp A (2001) Extramedulläre Osteosynthesetechnik bei proximaler Femurfraktur. Chirurg 72:1271–1276 Parker MJ, Handoll HHG (2001) Gamma and other cephalocondylic intramedullary nails versus extramedullary implants for extracapsular hip fractures (Cochrane Review). In: The Cochrane Library, Issue 2

References Pauwels F (1984) Hüftgelenksnahe Umstellungsosteotomien. In: Hierholzer G, Müller KH (Hrsg) Korrekturosteotomien nach Traumen an der unteren Extremität. Springer, Berlin, S 117 Rapp M (2008) Die instabile intertrochantäre 31 A 3.3Fraktur des proximalen Femurs – operative Verfahren und Behandlungsergebnisse. (Dissertation in Vorbereitung) Rapp M, Dittel KK, Schier H (1995) A new dynamic angle-adapted device – an innovative method for stabilizing proximal fractures of the femur. Br J Surg 82 (Suppl 1):119 (Abstract) Rapp M, Dittel KK, Felenda MR (2000) Die Dynamische Martin Schraube (DMS) als Implantatalternative zur Stabilisierung supracondylärer Femurfrakturen. 35. Jahrestagung der Österreichischen Gesellschaft für Unfallchirurgie, Salzburg/Österreich. Acta Chirurgica Austriaca 32 (Suppl 161): 71–75 Rapp M, Miller WO, Dittel KK, Abendschein W (1998) The variable angle compression hip system. 12. Internationaler Kongress „Osteosynthese International 1998“ des Gerhard-Küntscher-Kreises eV, Stuttgart. Abstract-Band 156 Rapp M, Dittel KK, Eberhard HJ, Miller WO (1998) Eine innovative Methode zur Stabilisierung instabiler intertrochantärer Umkehrfrakturen des proximalen Femurs (31A3.3). 12. Internationaler Kongress „Osteosynthese International 1998“ des Gerhard-Küntscher-Kreises eV, Stuttgart. AbstractBand 70 Rapp M, Eberhard HJ, Dittel KK, Miller WO (1999) Eine innovative Methode zur Stabilisierung instabiler intertrochantärer Umkehrfrakturen des proximalen Femurs (31 A 3.3). Jubiläumskongress „Osteosynthese International 1998“ des GerhardKüntscher-Kreises eV, Stuttgart. Osteosynthese International 7 (Suppl 2):47–51 Ruff ME, Lubbers LM (1986) Treatment of subtrochanteric fractures with a sliding screw-plate device. J Trauma 26:75 Sanders R, Regazzoni P (1989) Treatment of subtrochanteric femur fractures using the dynamic condylar screw. J Orthop Trauma 3:206 Schmickal T, Wentzensen A (1999) Implantatversagen – biologische oder mechanische Ursache? Akt Traumatol 29:28–32 Schröder D, Kiel G, Ungeheuer E (1986) Die Pohlsche Laschenschraube zur operativen Behandlung der Schenkelhalsfraktur. Akt Traumatol 16:71–73 Schumpelick W, Jantzen PM (1955) A new principle in the operative treatment of trochanteric fractures of the femur. J Bone Jt Surg 37-A:693–703

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Schwab E, Höntzsch D, Weise K (1998) Die Versorgung instabiler per- und subtrochantärer Femurfrakturen mit dem Proximalen Femurnagel (PFN). Akt Traumatol 28:56–60 Stürmer KM et al (1993) Wandel bei der Osteosynthese pertrochantärer und subtrochantärer Femurfrakturen. In: Rehm KE (Hrsg) Hzd Unfallchir, H232. Springer, Berlin Heidelberg, S 99–121 Stürmer KM, Dresing K (1995) Pertrochantäre Frakturen. Zbl Chir 120:862–872 Taylor JC, Russell TA (1992) Subtrochanteric fractures of the femur. Skeletal Trauma 45:1491 Tencer AF, Johnson KD, Johnston DWC, Gill K (1984) A biomechanical comparison of various methods of stabilization of subtrochanteric fractures of the femur. J Orthopaedic Res 2:297 Tönnis D (1984) Die angeborene Hüftdysplasie und Hüftluxation im Kindes- und Erwachsenenalter. Springer, S 171 Wagner H (1977) Korrekturosteotomie. Orthop 6:145 Wagner H, Wagner M (1994) Intertrochantere Osteotomien und Winkelplatte. In: Bauer T et al (Hrsg) Orthopädische Operationslehre 2/I. Thieme, Stuttgart, S 136 Wagner S, Rüter A (1999) Per- und subtrochantäre Femurfrakturen. Unfallchirurg 102:206–222 Warwick DJ, Crichlow TPKR, Langkamer VG, Jackson M (1995) The dynamic condylar screw in the management of subtrochanteric fractures of the femur. Injury 26:241 Weise K, Schwab E (2000) Osteosynthesen am proximalen Femur. OP-Journal 16:252–258 Weise K, Schwab E (2001) Intramedulläre Kraftträger zur Versorgung der per- und subtrochantären Femurfraktur. Chirurg 72:1277–1282 Weise K, Schwab E (2001) Intramedulläre Kraftträger zur Versorgung der per- und subtrochantären Femurfrakturen. Chirurg 72:1277–1282 Wipperman B (2001) Diagnostik und Therapie von Knochenmetastasen. Chirurg, S 40 Wirbel R, Mutschler WE (1995) Die chirurgische Therapie von Knochenmetastasen. Zentralbl Chir 120:707–712 Wolter D (1982) Osteolysen – Pathologische Frakturen. Thieme, Stuttgart, S 11–12 Woltmann A, Fischer W, Kujath P, Müller G, Bruch HP (1994) Letalität bei proximalen Femurfrakturen des alten Menschen. Unfallchirurgie 20:211–215 Zagrodnick J, Kaufner H-K (1990) Risikominderung durch differenzierte Wahl des Operationszeitpunktes bei der hüftgelenksnahen Femurfraktur des alten Menschen. Unfallchirurgie 16:139–143

177

Subject Index

A abnormal radiographic anatomy 29 access – dorsal mailbox 52 – lateral, Bauer 52 additional valgus osteotomy 96 adduction fractures 32 adjustable hip compression screw 17, 18, 19 adjustable worm gear 51 alendronate 166 anatomic reconstruction 101 angle adapted – contoured fit 3 – plate 10 – precision fit 75 – stable 173 – stepless 95 angle adjustment 21 – – individual 75 angle blade plate 9, 95 – 958 85 antibiotic – pharmacokinetics 133 – prophylaxis 130, 131 – selection 132 antiphospholipid syndrom 138 AO-classification – femur neck fractures 48 – femur fractures, intertrochanteric 77 – fracture 62 – – trochanteric 48 AO-nail 9 APC resistance 138 arthritis – degenerative 42 – – destructive 43 – posttraumatic 111 articular cartilage, thinning 41 aseptic femur head necrosis 73 – of the adolescent 95 avascular necrosis 64 – of femur head 61, 111

B bicondylar knee prosthesis 119 bilateral intertrochanteric femur fraction 120, 123 biochemical markers of bone turnover 165 bisphosphonate 166 – adverse effects 168 bleeding complications 140 bleeding risk 140 blood flow velocity 137 Boehler 8 bonding osteosynthesis 108, 109, 110 bone lesions, osteolytic 109, 110 bone tumors, primary 107 bone turnover – markers 163 – – biochemical 165 bones osteoporotic 85 bony consolidation 80 bridging of fragments 80

C calcar femoral 29, 39 calcitonin 165 calcitriol 164 calcium 163 calcium intake, daily 164 capacity, full weight bearing 71 causative pathogens 130 choice of device 101 classification – AO – – femur neck fractures 48 – – femur fractures, intertrochanteric – – fracture 62 – – – trochanteric 48 – by Garden 29 – by Haeuser 30 – by Pauwels 29, 30 – by Sennheiser 85 – fractures 45 – – subcapital 29 comminuted fracture zones 85 complications 74

77

180

]

Subject Index

compound osteosynthesis 107 compression osteosynthesis 51 compression plates, dynamic 10 compression principle, dynamic 75 958 condylar angle plate 74 congenital coxa valga 95 congenital femur neck pseudarthrosis 95 congenital hip roof dysplasy 95 congruent adjustability 22 connection, rigid 8 constant stress 15 contamination, microbial 130 contamination, perioperative bacterial 130 Cooper 61 correction, valgus or varus 75 cortical bone 161 cortical rim 31 coxa valga, congenital 95 cutting off 155 cutting out 71, 73, 79, 88 – secondary 159 cyclic threshold bending 15 cysts, subchondral 41

D decubitus, precaution against 145 deep venous thrombosis 80, 143 defect over bridging 108 deficiency – of antithrombin 138 – of protein C 138 – of protein S 138 deformities of the femoral head 43 degenerative arthritis 42 Denosumab 169 deperiostation 86 destructive degenerative arthritis 43 deterioration of bone, microarchitectural 161 distal femur fractures 101, 119 distal femur spiral shaft fractures 105 diuretics 169 – loop 169 double dynamic stabilization 3, 10, 75, 81 – angle-adapted contoured 24 – sliding link principle 24 dynamic compression plates 10 dynamic compression principle 75, 81 Dynamic Condylar Plate (DCS) 85 Dynamic Hip Screw (DHS) 10, 16, 18, 19, 61, 85 Dynamic Martin Screw (DMS) 2, 10, 21, 22, 47, 71, 72, 73, 81, 86, 87, 88, 95, 107 – double dynamic stabilization 24 – – angle-adapted contoured 24 – – sliding link principle 24 – individual patient specific shaft congruence 24 – infinitely variable neck/shaft angle 24 – intermediate 69

– intraoperative axis connection 24 – lag screw 22 – plates 21 dynamic self compression 9 dynamic sliding device 51 dynamic sliding tongue principle 80

E early functional therapy 11 Ender 8 endoprosthetic replacements 108 epiphysiolysis of the hip head 95 estrogen receptor modulators, selective (SERMs) 165 estrogen replacement therapy (ERT) 163, 164 etidronate (editronate) 166 Evans 77 exceptional indications 117 extension table 52 extraarticular metaphyseal wedge fracture 117, 119 extramedullary Femur Neck-Prosthesis 72 extramedullary implants – congruent adjustability 22 – rotary stability 22 – sliding functionality 22 extramedullary osteosynthesis 85

F factor V Leiden mutation 138 Feltenkrais 148 femur fraction – bilateral intertrochanteric 120 – distal 119 – pathological trochanteric 110 – subtrochanteric 51 femur fracture – 31 A-3 femur fractures, unstable 71 – bilateral intertrochanteric 123 – distal 3, 101 – imminent pathological subtrochanteric – intertrochanteric 51 – intertrochanteric 76, 82 – – AO-classification 77 – – instable reversed 79 – – reversed 78, 83 – – unstable 77 – pathologic 108 – pertrochanteric 71 – – reversed 37, 38 – proximal 3, 7, 77, 80 – subtrochanteric 39, 87, 89, 90 – – spiral 92 – – unstable 77 – supracondylar 51, 104

109

Subject Index femur head – deformities 43 – necrosis 31, 39, 63, 64, 113, 157 – – aseptic 73 – – – adolescent 95 – – avascular 61, 111 – metastases 39 – perforation 156 – prosthesis, metaphyseal (DMP) 73 – pseudarthrosis 39 femur nail, proximal (PFT) 74 – system 10 femur neck fracture 61, 67, 69 – AO-classification 48 – medial 51, 65 – metastases 39 – pathological 70 femur neck fragment, valgus reduction 75 femur neck prosthesis 111, 113 – extramedullary 72 femur neck pseudarthrosis, congenital 95 femur plate, adjustable 173 femur replacement, proximal 79 femur shaft fracture – proximal 85, 91 – spiral, distal 105 femur, subtrochanteric 85 fluoride 168 fondaparinux 138, 139 forensic aspects of thromboprophylaxis 141 fork-bolt connection 17 formation, metastatic 107 fracture classification 45 – Garden 62 – Pauwels 62 fracture 29 – 31 A 3-3 fracture 77 – – unstable 71 – compression 57 – extravertebral 167 – fixation, intraoperative 51 – hip 167 – in the hip joint area 2 – intertrochanteric 71 – of the proximal femur 29 – pathologic 101, 107 – – imminent 108 – – in the part of femur 107 – Pauwels III 50 – pertrochanteric, reversed 32 – sintering 80 – supracondylar 101 – trochanteric, AO-classification 48 – unstable 85 – vertebral 167 – zones, comminuted 85 full load capacity 80 full weight bearing capacity 71

G gamma nail 85, 123 Garden 29 Garden, fracture classification 62 Goetze 8

H Haeuser 29 Haeuser classification 30 head-neck fragment, valgisation 51, 80 headpreserving osteosynthesis 61 hematoma, precaution against 145 heparin-induced osteoporosis 141 heparin-induced thrombocytopenia (HIT) – non immunological 140 – type II (HIT II) 140 high energy trauma 85 hip compression screw (HCS) 15 – adjustable 17, 18, 19 hip – compression screw (HCS), rigid 17 – fractures 167 – head, epiphysiolysis 95 – post-traumatic osteoarthritis 61 – prosthesis 117 – roof dysplasy, congenital 95 – screw system, dynamic 10 – screw, dynamic (DHS) 61 hypercoagulability 139

140

I ibandronate 167 ideal shaft congruence 75 imminent pathological subtrochanteric femur fraction 109 implant dislocation 158 implant failure 71, 73 implantation, metaphyseal 111 indications, exceptional 117 indirect reposition techniques 86 individual angle adjustment 75 individual patient specific shaft congruence 24 infection 129 – postoperative 129, 130 infinitely variable neck/shaft angle 24 inflammatory complications, post-operative 39 instable reversed intertrochanteric femur fractures 79 intermediate DMS 69 intertrochanteric femur fracture 51, 76, 82 intertrochanteric osteotomy 95, 96 intertrochanteric proximal femur fracture 123 intertrochanteric reversed femur fracture 78, 83

]

181

182

]

Subject Index

intertrochanteric valgisation osteotomy 97, 99 intertrochanteric varisation osteotomy 98 intramedullary elastic round nails 8 intramedullary osteosynthesis 85 intraoperative axis connection 24 intraoperative fracture fixation 51 intraoperative valgus correction 3, 75

J

methicillin-resistant staphylococci (MRSA) 132 methylmethacrylate (PMMA) 107 microbial contamination 130 microfracture 41, 44 microarchitectural deterioration of bone 161 monosodiumfluorophosphate 168 Morbus Perthes 95 mortality, perioperative 75, 80 Müller 9 multidose vials 139

Jewett 8 N K

nail – AO-nail 9 – femur nail, proximal (PFT) 74 – – system 10 – gamma 85, 123 – intramedullary elastic round 8 – proximal femur nail (PFN) 74, 85 – – long 123 – tri-flanged-nail 8 neck fracture, pseudarthrosis 61 necrosis 44 – avascular 64 – femur head 31, 63, 64, 113, 157 – – aseptic 73 – post-traumatic 31 non union case 111 non-locking connection 1 nutrition 163

Kaplan-Maier-Survival-Graph 62, 63 Kathepsin-K-inhibitors 169 knee motion 102 knee prosthesis bicondylar 119 Kuentscher 64

L lag screw, positioning 66 lamellar pin, triple 8 late loosening 73 lesions, osteolytic 107 load bearing process 10 load bearing stability 87 load capacity 15 load stability 75 loop diuretics 169 low-molecular-weight heparins (LMWH) lung embolism 143

138, 139

M malpositioned supporting screw management, postoperative 102 markers for bone turnover 163 Martin Screw, dynamic 2 McLaughlin 8 measures – pharmacological 138 – thromboprophylactic 137 medial femoral neck fractures 51, 65 metal-cement-complex osteosynthesis 102, 107 metaphyseal femur head prosthesis (DMP) 73 metaphyseal implantation 111 metastases – of non-osseous tumors 107 – osteolytic 39 metastatic formation 107 methicillin-resistant coagulase-negative staphylococci 132

O operative procedure 50 oscillation test 15, 18 osteochondrosis 95 osteolysis 107 osteolytic bone lesions 109, 110 osteolytic lesions 107 osteolytic metastases 39 osteomalacia 164 osteoporosis 107, 161 – heparin-induced 141 – loss of cortical bone 161 – loss of trabecular bone 161 – prevention 162, 163 osteoporotic bones 85 osteosynthesis – bonding 108, 109, 110 – compound 107 – extramedullary 85 – headpreserving 61 – intramedullary 85 – metal-cement-complex 102, 107 – sequential 121

Subject Index osteotomy – intertrochanteric 95, 96 – supracondylar 101

P Paget’s disease 165 – treatment 168 parathyroid hormone (PTH) 168 pathogens, causative 130 pathologic femur fractures 108 – trochanteric 110 pathologic fracture 101, 107 – imminent 108 – in the part of femur 107 Pauwels 29, 51 Pauwels III fracture 95 Pauwels, fracture classification 30, 62 Penicillin 132 perioperative bacterial contamination 130 perioperative mortality 75, 80 periosteal stripping 102 pertrochanteric femoral fracture 71 – reversed 32, 37, 38 pharmacokinetics of antibiotics 133 pharmacological measures 138 phlebographic screening 137 physical activity 163 physical methods of prophylaxis 138 physiotherapy 143 – early 144 – postoperative 103 phytoestrogen 169 pinion tongue mechanism 22, 23 Pipkin 29 plate loosening 71 plate system 1 Pohl 1, 8 Pohl’s concept 9 Pohl’s implant 123 Pohl’s sliding barrel plate 9 Pohl’s sliding cylinder 1 Pohl’s system 2, 10 postoperative infection 129, 130 postoperative management 102 postoperative physiotherapy 103 posttraumatic arthritis 111 post-traumatic necrosis 31 post-traumatic osteoarthritis of the hip 61 precaution against – decubitus 145 – hematoma 145 – thrombosis 145 precision fit, angle-adaptable 75 prevention, osteoporosis 162, 163 primary bone tumors 107 procedure, technique 50

prophylaxis 129 – antibiotic 130, 131 – physical methods 138 – surgical antimicrobial 132 – femur neck 111, 113 prosthesis – hip 117 – knee bicondylar 119 prothrombin G2010A mutation 138 proximal and distal femur fractures 3 proximal femur fracture 7, 77, 80 – intertrochanteric 123 proximal femur nail (PFN) 74, 85 – long 123 proximal femur nail systems 10 proximal femur replacement 79 proximal femur shaft fracture 85, 91 pseudarthrosis 73, 79, 98 – of the neck fracture 61 – subtrochanteric 153 pseudocyst, subchondral 41 Pseudomonas aeruginosa 130

R radioanatomy 27 radiographic anatomy, abnormal 29 raloxifene 165 RANK/RANKL system, inhibitors 169 reactive sclerosis 43 reconstruction, anatomic 101 reosteosynthesis 74 replacement therapy, estrogen (ERT) 163, 164 replacements, endoprosthetic 108 reposition techniques, indirect 86 reversed pertrochanteric femoral fracture 37, 38 reversed pertrochanteric fractures 32 revisional management 153 rigid connection 8 rigid hip compression screw 17 risedronate 166 risk factor of thrombosis 137 risk of deep vein thromboembolism (VTE) 137 rotation malpositioning 73, 79 rotation stability 22, 85

S S. epidermidis 130 Sauerbruch 8 Schneider 9 sclerosis – reactive 43 – subchondral 41 second bang 123 selection of antibiotics

132

]

183

184

]

Subject Index

selective estrogen receptor modulators (SERMs) 165 self compression 1 – dynamic 9 Sennheiser, classification 85 sequential osteosynthesis 121 shaft congruence, ideal 75 Simon-Weidner 8 sintering of the fractures 80 sintering in the fracture area 88 skeletal study, triple-phase 44 sliding barrel plate 57 sliding barrel principle 2 sliding compression principle 75 sliding device, dynamic 51 sliding functionality 22 sliding link principle 1, 2, 10, 51, 173 sliding tongue principle 3 sliding tongue system 24 Smith Peterson 8 sodium fluoride 168 stabilization, double dynamic 3, 10, 75, 81 stable fracture fixation 1 staphylococci, methicillin-resistant (MRSA) 132 – coagulase-negative 132 Staphylococcus aureus 130 static test 15 – results 16 statistical items 47 stepless angle adaption 95 Stürmer 71 subcapital fractures, classification 29 subchondral cysts 41 subchondral pseudocyst 41 subchondral sclerosis 41 subtrochanteric femoral fracture 39 subtrochanteric femur 85 subtrochanteric femur fraction 51 subtrochanteric femur fractures 87, 89, 90 – spiral 92 subtrochanteric pseudarthrosis 153 supporting screw 51, 56 – malpositioned 159 supracondylar femur fractures 51, 101, 104 supracondylar osteotomy 101 surgical antimicrobial prophylaxis 132 surgical technique 49, 52 surgical wound healing 129 systemic antibiotics 129

T tamoxifene 165 technique, surgical 49, 52 teicoplanin 132 telescoping 58, 71 teriparatide 168 test – oscillation test 15, 18

– static test 15 – – results 16 therapy 129 – early functional 11 thiazides 169 Thornton 8 three-point-gait 144 thrombocytopenia, heparin induced (HIT) 140 – non immunological 140 – type II (HIT II) 140 thromboprophylactic measures 137 thromboprophylaxis 143 – forensic aspects 141 thrombosis – precaution against 145 – risk factor 137 tiludronate 168 trabeculae in the hip joint region 29 trabecular bone 161 trabecular groups 30 – after Greenspan 30 – of the head and neck 29 tri-flanged nail 8 triple lamellar pin 8 triple-phase skeletal study 44 trochanteric fractures, AO-classification 48 tube length 21 tumors, non-osseous, metastases 107

U unstable fractures 85 – 31 A 3-3 femur 71 – intertrochanteric femur 77 – subtrochanteric femur 77

V valgisation angle 51 valgisation of the head-neck fragment valgisation osteotomy, intertrochanteric valgus correction, intraoperative 3, 75 valgus or varus correction 75 valgus osteotomy – additional 96 – intertrochanteric 96, 100 valgus reduction, femur neck fragment vancomycin 132 varisation osteotomy, intertrochanteric varus, intertrochanteric osteotomy 96, venous polling 137 venous thromboembolism (VTE) 137 – deep, risk 137 – prophylaxis 137 venous thrombosis, deep 80

51, 80 97, 99

75 98 100

Subject Index Vitamin D 163 – deficiency 164 Vitamin K antagonist 138, 139

W Ward’s triangle 29 Watson-Jones 8 wedge fracture, extraarticular metaphyseal 117, 119 weight bearing 144 woman, postmenopausal 161 worm gear 17 – adjustable 51

worm gear adjustment 75 worm gear mechanism 3, 22, 23, 24, 66 – pinion tongue 22, 23 worm-wheel 17 wound healing, surgical 129 wound infection 129 – deep 131

Z zolendronate 167

]

185