B.G.Weber THE F. Magerl

EXTERNAL FIXATOR AO/ASIF-Threaded Rod System Spine-Fixator

With a Chapter by Ch. Brunner

Foreword by A. Sarmiento

With 362 Partly Colored Figures

Springer-Verlag Berlin Heidelberg New York Tokyo 1985

Prof. Dr. BERNHARD G. WEBER Dr. FRIEDRICH MAGERL Dr. CHRISTIAN BRUNNER

Klinik für Orthopädische Chirurgie, Kantonsspital, CH-9007 St. Gallen

Translated from the German by TERRY C. TELGER

Tit1e of the German Edition B.G. WEBER' F. MAGERL: Fixateur exteme © Springer-Verlag Berlin Heidelberg 1985

ISBN -13: 978-3-642-70017-0

ISBN-13: 978-3-642-70017-0 DOI: 10.1007/978-3-642-70015-6

e-ISBN-13:978-3-642-70015-6

Library of Congress Cataloging in Publication Data. Weber, B.G. (Bernhard Georg), 1927- . The external fixator. Translated from the German with title: Fixateur externe. Ineludes bibliographies and index. 1. External skeletal fixation (Surgery) 1. Magerl, F. (Friedrich), 1931- . II. Brunner, Christian Ferdinand, 1937-III. Title. IV. Title: Spine-fixator. [DNLM: 1. Fracture Fixation - methods. WE 185 W373e] RD103.E88W43 1985 617'.15 84-24045

This work is subject to copyright. All rights are reserved, whether the whole or parts of the material coneemed, specifically those of translation, reprinting, re-use of illustrations, broadcasting, reproduction by photocopying machine or similar means, and storage in data banks. Under § 54 of the German Law where copies are made for other than private use, a fee is payable to "Verwer­tungsgesellschaft Wort", M unich.

© by Springer-Verlag Berlin Heidelberg 1985 Softeover reprint of the hardeover 1st edition 1985

The use of general descriptive names, trade marks, etc. in this publication, even if the former are not especially identified is not be taken as a sign that such names as understood by the Trade Marks and Merchandise Marks Act, may accordingly be used freely by anyone.

Reproduction of the figures: Gustav Dreher GmbH, Stuttgart

2124/3130-543210

Foreword

Professor B.G. WEBER has once again and in a very timely fashion produced a superb book on an orthopaedic subject of great importance. "The Extemal Fixator" is the most comprehensive text on the subject in orthopaedic literature to date. Professor WEBER

thoroughly discusses extemal fixation with c1arity, organization, profuse illustrations and roentgenograms.

Professor WEBER acknowledges that the use of extemal fixation in orthopaedic surgery is not newand traces its history over the years. He points out c1early the fact that though at various times the "method" has experienced periods of disrepute, modem sophistication, improved technology and a better understanding of its philosophy have given the system a newand perhaps permanent place in the armamentarium of the orthopaedic surgeon.

All methods of treatment have critics as well as supporters, and not infrequently the strongest criticisms are the result of poor understanding of the philosophy proposed and its proper implementation. Professor WEBER, in his carefully detailed and well illustrated book, has made it abundantly c1ear that the use of extemal fixators in the treatment of fractures must be c1early understood by the orthopaedic surgeon in order to obtain satisfactory clinical results. His discussion of its philosophy, pathomechanics and technology are most comprehensive and leave "no stone untumed" and because of this the book represents a most comprehensive text on the subject.

I have long held the belief that immobilization in the treatment oflong bone fractures is unphysiological and that fracture care should avoid, as much as possible, rigid fixation of fracture fragments. I recognize, however, there are situations where the creation of a healthy environment in which controlled motion is present cannot be attained. Severely open fractures and certain nonunions are representative examples of that situation. It is primarily in these circumstances where rigid fixation may be the treatment of choice. Extemal fixation, as Professor WEBER has so well documented, is an excellent method to obtain osseous repair while maintaining function and cosmesis.

AUGUSTO SARMIENTO, M.D. Professor and Chairman Department of Orthopaedics University of Southem California School of Medicine

Preface

The use of an external fixation device for the stabilization of bone fragrnents probably dates back to LAMBOTTE in 1902. But despite its long history, the external fixator has not gained the same degree of acceptance in fracture management as the" elosed" meth­ods of BÖHLER, WATSON-JONES and SARMIENTO, or true internaI fixation.

Operative fracture treatment itself was not widely practiced until it was popularized in 1958 by the Swiss Association for the Study ofInternal Fixation (ASIF). It is important to note that the principal authors of the ASIF technique, Drs. MÜLLER, ALLGÖWER and WILLENEGGER, have never represented their technique as the only "correet" one, and in the preface to their book Technique of Operative Fracture Management (Springer­Verlag, 1963) they state, "We caution very strongly against internaI fixations performed without proper training, instrumentation and surgical asepsis ... " The potential risks of internaI fixation have sparked renewed interest in conservative treatment strategies, with the resuIt that SARMIENTO'S "functional bracing" technique is now practiced as widely as the ASIF method.

But neither internaI fixation nor functional bracing is adequate for the management of the highly complex extremity injuries that are being seen with increasing frequency as a resuIt of motorcyele and other high-speed vehicular accidents (" Honda disease "). This accounts in large part for the many reeent artieles and books devoted to the subject of external skeletal fixation (BROOKER, EDWARDS 1979; UHTHOFF 1982; MEARS 1983; ACKROYD, O'CONNOR, DE BRUYN 1983). The shear volume of these publications suggests that the external fixator is being "rediscovered" in the English-speaking world after ANDERSON put the external fixation concept into practice in the United States in 1934.

When the first ASIF book was published in 1963, Dr. MÜLLER and other Swiss orthopedic surgeons had already been practicing external fixation for some years -first in reconstructive orthopedics and later fracture management. The threaded-rod external fixator, for example, is described in the first ASIF book.

At the Department of Orthopedic Surgery of Kantonsspital St. Gallen, Switzerland, external fixations with the threaded-rod device have become as routine as internaI fixa­tions by the ASIF method. This" routineness" mayexplain why no major publications on external fixation have yet appeared in Switzerland, and we feel that a text on the subject is overdue. In the present book we shall examine the use of the external fixator not only in fracture treatment, but also in other areas of orthopedic surgery.

The following colleagues had a hand in the preparation of the book: Mrs. URSULA OETLIKER and Mrs. MYRTHA ZWEIFEL, who undertook repeated typescript revisions with thireless diligence and technical expertise; KATRIN and HORsT SCHUMACHER, who pre­pared the excellent drawings; and Mrs. MARIANNE SCHAFFNER, Mrs. DORIS CLERICI and Mrs. ANNELISE SPITZ, who prepared the photographic illustrations.

I express special thanks to my elosest medical colleagues: Dr. FRITZ MAGERL, assis­tant department head, who described the spin al external fixation device; and Dr. CHRIS­TIAN BRUNNER, chief of pediatric orthopedics, who wrote a chapter on external fixations in children and adolescents.

VIII Preface

I am also grateful to my present and former straff eolleagues who "tended to busi­ness" on the c1inieallevel.

In his eapaeity as engineer and manufaeturer, Dr. h.e. ROBERT MATHYS has worked elosely with the Teehnieal Committee of the ASIF and with us to improve the quality of the surgieal armamentarium. His work is gratefully aeknowledged.

Finally, I express thanks to the staffat Springer-Verlag, who onee again did outstand­ing work in the publieation of this text.

St. Gallen, Summer, 1984 B.G. WEBER

Contents

Preamble. B.G. WEBER . . . . . . . . . . . . . . . . . . . . . . . . .. 1

The ASIF Threaded External Fixator in General Orthopaedic and Trauma Surgery of the Extremities

A General Part. B.G. WEBER

1 Introduction . . . . . . 2 The History of External Fixation 3 Bone Healing in the Presenee of an External Fixator

3.1 Healing of a Diaphyseal Fraeture 3.1.1 Primary Healing of the Cortex 3.1.2 Seeondary Healing of the Cortex 3.1.3 Nonunion . . . . . . . . . . 3.1.3.1 Pathogenesis of Vaseular Nonunion 3.1.3.2 Pathogenesis of Avaseular Nonunion

3.2 Healing of Caneellous Bone .. .. 3.2.1 Primary Healing of Caneellous Bone 3.2.2 Seeondary Healing of Caneellous Bone 3.2.3 Nonunion of Caneellous Bone 3.2.3.1 Pathogenesis of Vaseular Nonunion . 3.2.3.2 Pathogenesis of Avaseular Nonunion

3.3 Healing of Nonunions . . . . . . 3.3.1 Healing of a Vaseular Nonunion 3.3.2 Healing of an Avaseular Nonunion 3.3.3 Healing of a Nonunion with Bone Loss

4 Goals of Treatment with the External Fixator

4.1 4.2 4.3 4.4

Lengthening Frame . Neutralization Frame Compression Frame Soft-Tissue Frame

B On the Biomechanics of External Fixation. B.G. WEBER

1 Intrinsie Stability of the External Fixator . . . . . . 2 The External Fixator and Bone as a Composite System

2.1 Extemal Fixation without Interfragmental Contaet 2.2 Extemal Fixation with Interfragmental Contaet . . 2.3 Extemal Fixation with Interfragmental Compression 2.4 Biomeehanies and Seleetion of the Frame ....

4

4 6 7

9

9 9

12 12 14

14 14 14 14 14 14

20 20 20 20

26

26 26 26 26

27

27 28

28 28 31 32

X Contents

3 Stress Transfer with the External Fixator

3.1 Stress Transfer with the Neutralization and Lengthening Frame 3.2 Stress Transfer in the Presence of Bone Contact 3.2.1 Stress Transfer with a Bilateral Compression Frame . 3.2.2 Stress Transfer with a Unilateral Compression Frame 3.2.2.1 "Prebending" of the Rod . . . . . . . . 3.2.2.2 "Prebending" of the Bone . . . . . . . . . . . 3.2.2.3 Axial Compression with a "Spreading Rod" . . .

4 Means of Augmenting the Stability of the External Fixator

4.1 Increasing the Number of Pins or Screws 4.2 Placement of the Pins and Screws 4.3 Increasing the Number of Rods . 4.4 The Double-Frame Configuration 4.5 The Biplanar Frame .....

5 Improving the Anchorage of Pins and Screws in Bone

6 Restoring the Compressive Strength of Bone in the Absence of Interfragmental

34

34 34 34 34 34 37 37

38

38 38 38 40 41

42

Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

6.1 6.2 6.3

Restoring Bone Contact by Shortening .............. 45 Restoring Bone Contact by Interposing a Pressure-Resistant Bone Graft 46 Restoring Bone Contact by Adjunctive InternaI Fixation 46

6.3.1 6.3.2 6.4 6.5 6.6

Lag Screw pIus External Fixation . . . . . . . . . AntigIide Plate pIus External Fixation . . . . . . . Restoring Bone Contact by Cancellous Bone Grafting Restoring Bone Contact by Transverse Compression Restoring Bone Contact by Fragment Manipulation .

7 Sagittal or "Intermediate" Screw Placement in Unilateral External Fixation of the Tibia .................. .

8 Summary of the Biomechanics of External Fixation

8.1 The External Fixator and Bone . 8.2 Unilateral or Bilateral Frame . . 8.3 Elasticity of the External Fixator

e The Threaded External Fixator. Instrumentation. B.G. WEBER

1 Introduction

1.1 Requirements of the External Fixator 1.2 The External Fixator of the ASIF . .

2 The Elements of the Threaded External Fixator

47 48 49 51 51

52 53

53 53 53

54

54

54 54

55

2.1 Steinmann Pins . . . . . . . . . . . 55 2.2 Schanz Screws . . . . . . . . . . . 55 2.3 The 4.5-mm and 3.5-mm Cortex Screws 55 2.4 Drill Bits, Drill Sleeyes and Taps 56 2.5 Clamps for Steinmann Pins, Schanz Screws, 4.5-mm and 3.5-mm Cortex

Screws 56 2.6 Threaded Rods 56 2.7 Nuts 56 2.8 Siider Bar 56

2.9 Additional lnstruments and lmplants 2.10 Special lnstruments

3 The Threaded Minifixator

D Operative Technique for the Threaded External Fixator. B.G. WEBER

1 The Special Characteristics of the Threaded External Fixator 2 Errors of Pin and Screw lnsertion . .

2.1 Technique for Steinmann Pins 2.2 Technique for Schanz Screws 2.3 Technique for Cortex Screws

3 Reduction

3.1 Concept. 3.2 Technique

4 The Application of a Bilateral Frame

4.1 Pin Placement 4.2 Pin lnsertion . . . . 4.3 Assembling the Frame 4.4 Reinforcing the Frame 4.5 Finishing the Frame

5 The Application of a Unilateral Frame

5.1 Placement of the Schanz Screws 5.2 Screw lnsertion . . . . . . . 5.3 Assembling the Unilateral Frame 5.4 Reinforcing the Frame 5.5 Finishing the Frame .....

E Teehniques for Reinforeing the External Fixator. B.G. WEBER

1 lncreasing the Number of Rods . . . . . . . . . . . . . 2 Mounting Additional Rods in a Perpendicular Configuration 3 Stability of the Unilateral Frame .... 4 Restoring Bone Contact . . . . . . . . 5 Stability Enhancemerit and Frame Design

F Situations Requiring a Special Operative Technique. B.G. WEBER

1 Stabilization of Short Fragments ............ . 2 Diagonal Bracing Rod . . . . . . . . . . . . . . . . . . 3 Adding Single Clamps to the Frame, and Transverse Compression

G Axial Correetions. B.G. WEBER

1 Axial Corrections in the Bilateral Frame . 2 Axial Corrections in the Unilateral Frame 3 Axial Corrections with the Aid of an External Frame

H Loeal Care Following Frame Applleation. B.G. WEBER

1 Postoperative Care 2 Further Supervision . . . . . . . . . . . . . . .

Contents XI

58 58

59

60

60 60

61 63 64

66

66 68

69

69 70 72 72 72

74

74 75 78 79 79

80

80 80 81 83 85

86

86 87 88

89

89 93 93

94

94 95

XII Contents

I Duration of External Fixation, and Removal of the External Fixator. B.G. WEBER 96

1 General Duration of External Fixation . . . 96 2 Early Removal of Individual Pins or Screws 96 3 Staged Removal of Combined Frames . . . 97 4 Removal of the External Fixator ..... 97 5 "Dynamization" of External Fixator Frames 99

K Instrumentation Used with the Threaded External Fixator. B.G. WEBER 100

1 General . . . . . . . . . . 100 2 Threaded External Fixator Sets 100

L The Threaded External Fixator in Adults. Clinieal Examples. B.G. WEBER 106

1 2 3 4 5 6 7 8 9

10

Introduction Humerus Elbow Wrist Pelvis Femur Knee Tibia Ankle Soft Tissues

106 111 115 118 125 127 139 146 209 231

M The Threaded External Fixator in Children and Adolescents. CH. BRUNNER 243

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . .. 243 2 The External Fixator for Severe Open Fractures in Children, Infected Fractures

and Infected Nonunions . . . . . . . . . . . . . . . . . . 244 3 Corrective Osteotomies of the Proximal Femur in Small Children 252

3.1 3.2 3.3

Instrumentation and Technique . . . The Technique Practiced at our Center Indications and Examples .....

4 Lengthening Osteotomies in Children and Adolescents

4.1 4.2 4.3 4.4

Introduction . . . . . . . . . . . . Lengthening Osteotomy of the Humerus Lengthening Osteotomy of the Femur . Lengthening of the Tibia ..... .

5 Corrective Osteotomy for Staged Limb Lengthening

5.1 5.2 5.3

Staged Supracondylar Lengthening of the Femur Corrective Osteotomy of the Proximal Tibia Supramalleolar Corrective Osteotomy of the Tibia

6 Special Problems

252 252 254

259

259 259 261 269

273

273 275 281

284

N Concluding Remarks. B.G. WEBER .................... 287

Contents XIII

External Spinal Skeletal FixatioD. F. MAGERL

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 Classifieation and Prognosis of Spinal Injuries and Their Relevanee to

Stabilization . . . . . . . . . . . . . . . . . . . .

2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11

Wedge-Compression Fraeture ........ . Stable Burst Fraeture or Ineomplete Burst Fraeture Unstable Burst Fraeture of Complete Burst Fraeture Chanee Fraeture . . . . Flexion-Distraetion Injury Translational Injuries Remarks on Classifieation Classifieation and Mode of Treatment Degree of Stability ....... . Type of Instability and Prognosis . . Prognostie Signifieance of Angular Deformities

3 The ESSF Device and Instrument Set 4 Biomechanics of the ESSF Deviee . .

4.1 4.2 4.3 4.4 4.4.1 4.4.2

4.5 4.6 4.7 4.8 4.8.1 4.8.2 4.8.3

Open or Percutaneous Application of the ESSF Deviee The Importanee of Prestressing . . . . . . Use of the ESSF Device in the NeutraI Mode U se of the ESSF Device in Distraction Percutaneous Applieation ..... Open Applieation (Technique I-III) .

U se of the ESSF Device in Compression Stabilization of Fractures of the Fifth Lumbar Vertebra Translaminar Screw Fixation of Facet Joints Coupled ESSF Assemblies . . The Straight Coupled Assembly The Angled Coupled Assembly Application and Prestressing of Coupled Assemblies

5 Experimental Investigations 6 Indieations for the ESSF Device

6.1 6.2

Trauma .... Other Indications

290

291

292 292 293 293 294 294 296 296 296 297 297

298 300

300 300 301 301 301 302

302 303 303 304 305 305 306

307 308

308 308

7 Timing of Surgery . . . 309 8 Operative Technique: Trauma 310

8.1 Open Technique 310 8.1.1 Operating Table, Closed Reduction, Positioning 310 8.1.2 Approach . . . . . . . . . 310 8.1.3 Intraoperative Reduction ......... 310 8.1.4 Insertion of the Schanz Screws . . . . . . . 310 8.1.5 Instrumental Reduction, Distraction-Deeompression 313 8.1.6 Intraoperative Myelography . . . . . . . . . . 315 8.1.7 Lamineetomy, Op en Deeompression, Repair of Dural Laeerations 315 8.1.8 Stabilization of Posterior Elements, Translaminar Screw Fixation,

H-Graft, Tension Band Wiring . . . . . . . . . . . . . . . 316 8.1.9 Definitive Insertion of the Sehanz Serews, Caneellous Bone Grafting,

Wound Closure ....................... 316

XIV Contents

8.1.10 Assembly and Prestressing of the ESSF Deviee ........ 317 8.1.11 Open Technique with Caneellous Grafting of the Vertebral Body,

Posterior Interbody Fusion ................ 320

8.2 8.3

8.3.1 8.3.2

Pereutaneous Applieation of the Fixation Deviee ...... . Repositioning the Fixation Deviee, Combined Open and Pereutaneous Applieation ..... Repositioning the Deviee Combined Applieation

9 Operative Technique: Spondylitis

9.1 9.2 9.3

Two-Stage Proeedure with Direet Foeal Treatment Sernidireet Treatment Indireet Treatment

10 Postoperative Care and Postoperative Course

10.1 10.2 10.3

General Remarks Postoperative Management of Fraetures Postoperative Management of Spondylitis

321

322 322 322

322

323 324 324

325

325 327 328

11 Clinieal Examples ........ 328

11.1 Trauma ........ 328 11.1.1 Open Proeedure, Technique I 328 11.1.2 Op en Proeedure, Technique II 333 11.1.3 Open Proeedure, Technique III 338 11.1.4 Stabilization of the 5th Lumbar Vertebra with the ESSF Deviee 343 11.1.5 Open or Open-Pereutaneous Stabilization with the Simple ESSF Deviee

Over More than Two Motion Segments ............. 345 11.1.6 Stabilization of an Interbody Fusion with the ESSF Deviee . . . . . 345 11.1.7 Pereutaneous Applieation of the Simple ESSF Deviee or Coupled

Assembly . . . . . . . . . . . . . .. .......... 347 11.1.8 Example of a Complieation: Collapse of the Vertebral Body after

Removal of the ESSF Deviee . . . . . . . . 350

11.2 Spondylitis 351 11.2.1 Two-Stage Proeedure with Open Surgieal Treatment 351 11.2.2 Exeeption: Single-Stage Proeedure with Open Surgieal Treatment 351 11.2.3 Indireet Treatment of Spondylitis with Pereutaneous Applieation of the

ESSF Deviee 351

12 Results of Treatment

12.1 Fraetures. 12.1.1 Injuries . . . 12.1.2 Treatment 12.1.3 Results of Treatment 12.1.4 Complications . . .

12.2 Spondylitis . . . . 12.2.1 Causative Organisms, Loealization, Findings 12.2.2 Treatment .... 12.2.3 Results of Treatment 12.2.4 Complications . .

12.3 Other Indieations

360

360 360 360 360 361

361 361 361 362 362

362

Contents XV

13 Discussion of the Method of Treatment 363 14 Remarks . . . . . . . . . . . . . 365

References 367

Subject Index 371