Biomechanics of the Normal and Diseased Hip: Theoretical Foundation, Technique and Results of Treatment An Atlas

279 Pages·1976·25.076 MB·English

by  Professor Friedrich Pauwels Dr. med. Dr. med. h.c. Dr.-Ing. E.h. (auth.)

Friedrich Pauwels
Biomechanics of the
Normal and Diseased Hip
Theoretical Foundation, Technique and
Results of Treatment
An Atlas
J.
Translated by Ronald Furlong and Paul Maquet
With 305 Figures in 853 Separate Illustrations
Springer-Verlag
Berlin Heidelberg New York 1976
Professor Friedrich Pauwels
Dr. med. Dr. med. h.c. Dr.-lng. E.h.
Orthopaedic Surgeon
Zweiweiherweg 3, D-S100 Aachen
Translators:
Ronald John Fur/ong, MB, BS, FRCS Eng.
Hon. Consulting Orthopaedic Surgeon to St. Thomas's Hospital, London
Late Consulting Orthopaedic Surgeon to the Army
149 Harley Street, London W1, England
Paul Maquet, MD
Orthopaedic Surgeon
ste ste
Clinique Elisabeth and Clinique Rosalie, Liege, Belgium
Translation of the German edition 1973:
Atlas zur Biomechanik der gesunden und kranken Hujte
Prinzipien, Technik und Resultate einer kausalen Therapie
ISBN-13: 978-3-642-66214-0 e-ISBN-13: 978-3-642-66212-6
DOl: 10.1007/978-3-642-66212-6
Library of Congress Cataloging in Publication Data. Pauwels, Friedrich. Biomechanics of the normal and diseased hip.
- An atlas. Translation of Atlas zur Biomechanik der gesunden und kranken HUfte. Bibliography: p. Includes index.
1. Hip joint- Diseases. 2. Hip joint. 3. Human mechanics. 1. Title. [DNLM: 1. Biomechanics - Atlases. 2. Hip
Physiopathology - Atlases. 3. Hip- Surgery-Atlases. WE17 P336aJ. RC932.P3813. 617'.58. 75-31723
This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, 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 Copyright Law, where copies are made for other than
private use, a fee is payable to the publisher, the amount of the fee to be determined by agreement with the publisher.
© by Springer-Verlag Berlin Heidelberg 1976
Softcover reprint of the hardcover 1s t edition 1976
The use of 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.
To my wife Sibylle with gratitude
for 4 years ofu nderstanding collaboration
0
Preface
Orthopaedic surgery today is undergoing a phase of vara, pseudarthrosis of the neck of the femur, and osteo
turbulent development. Once the essential aim of treatment arthritis, even in cases which up to now would usually
consisted in restitution of anatomy by surgery in order to have been considered incurable.
restore function. Various forms of alloplasty have recently This atlas not only shows convincing results of such
become fashionable for the treatment of joint diseases. treatment. Above all, it gives interested clinicians a line to
The main reason for this vogue is that restoration of follow and sets out precise indications for the practical
normal anatomy improves function and alleviates pain steps of the operations.
only in certain special instances. I am especially grateful to Professor B. Kummer who, as
Alternatively, the implantation of artificial joints of an anatomist, acted as the devil's advocate, and subjected
different types has been presented as the method of the new concepts in functional anatomy and biomechanics
choice because the immediate results are often spectacular shown in the atlas to critical analysis.
to the patient and the operative technique is relatively I wish to express my sincere thanks to Professor
easily learned. Nevertheless, more and more voices are R.J. Furlong (London) and Dr. P. Maquet (Liege) not only
being heard, drawing attention to numerous bad results for the English translation, executed with so much accuracy
that appear after shorter or longer periods. In the first and deep understanding of the principles of biomechanics
instance, these failures consist of unexpected and undesir but also for their inestimable help in reading the proofs.
able reactions between the foreign material and the tissues Finally, I thank Springer-Verlag and their associates,
of the locomotor system. Bony resorption due to locally and particularly Dr. Gotze and Professor Geinitz, not only
exaggerated stressing plays an essential part. for the care they have used in creating this book, but also
A promising alternative to the use of prostheses and for the understanding and inexhaustible patience they have
the many problems arising therefrom is to make use of shown during its preparation.
the natural capacity for functional adaptation possessed by
the tissue of the skeleton. The principle of this method of
Aachen, October 1975 F. Pauwels
treatment is, by exact planning of the necessary alteration
of stress, to restore the biomechanical equilibrium be
tween the amount and type of mechanical stressing, on the
one hand, and the capacity of the tissue reaction to support
it on the other.
From this principle, a completely new conception of
treatment arises. When it is impossible to deal directly
with the cause of the disease, that is to say tissue insuf
ficiency, there is but one way open and that is to adapt the
mechanical stress to this insufficiency. This result is
achieved by reducing the mechanical stressing considerably
below the normal level, or by altering the quality of the
stressing in order to induce healing. Careful planning of
the operation and a specific operative technique are es
sential. When the indications are correct, the methods of
surgical treatment described here give lasting good results
in three important hip conditions, namely, congenital coxa
VII
Contents
I. Theoretical Foundation II. Biomechanical Analysis and Basic
Treatment of Congenital Coxa Vara,
Pseudarthrosis of the Femoral Neck,
1. Loading and Stressing. . . . . . . . . . 1
and Osteoarthritis of the Hip
2. Effect of Mechanical Stress on the Skeleton 3
a) Influence of Mechanical Stress on Mature
Bone ............... . 4
A. Congenital Coxa Vara
b) Influence of Type of Mechanical Stress on
the Differentiation of Supporting Tissue 5
1. Pathology and Biomechanics 42
3. Physiological Load on the Upper Extremity of
2. Principles of Treatment of Congenital Coxa
the Femur ............. . 8
Vara during the Growth Period . . . . . 52
4. Survey of the Types of Stress That Occur . . 10
a) Recurrences after the Neck/Shaft Angle Has
5. Influence of the Area of the Loaded Surface on Been Restored to Normal . . . . . . . . 52
the Magnitude of Stressing 13 b) Lasting Results Obtained by Adaptation of
the Mechanical Stress to Defective Tissue 55
6. Fundamental Stressing of a Long Bone 14
3. The Y Osteotomy as Basic Treatment 55
7. Physiological Stress at the Upper End of the
Femur 17 a) Definition and Consequences 55
b) Planning and Execution of the Operation 58
8. The Functional Architecture of the Upper End
c) Results of the Y Osteotomy . . . . . . 62
of the Femur ............ . 18
9. The Consequence of a Disturbance of the
Equilibrium between Tissue Resistance and
Mechanical Stressing . . . . . . . . . 21 B. Pseudarthrosis of the Neck of the Femur
10. Basic Treatment of the Three Conditions
1. Influence of the Type of Mechanical Stress on
Mentioned: Congenital Coxa Vara, Osteo
the Healing of a Fracture . . . . . . . 81
arthritis, and Pseudarthrosis of the Neck of the
2. Classification of Fractures of the Femoral
Femur 23
Neck from the Biomechanical Standpoint 83
11. The Influence of the Neck/Shaft Angle on the
3. The Special Case of the Abduction Fracture 85
Load and Stressing of the Upper End of the
Femur ................ . 24 4. Basic Treatment of Pseudarthrosis of the Neck
a) Influence of the Neck/Shaft (CCD) Angle on of the Femur by Alteration of the Type of
the Loading of the Upper End of the Femur 26 Mechanical Stress .......... . 86
b) Influence of the Neck/Shaft Angle on the
a) Reorientation of the Fracture Surfaces by
Stressing of the Upper End of the Femur . . 28 Intertrochanteric Wedge Osteotomy 86
12. The Trajectorial Structure of Cancellous Bone b) Planning and Technique of the Reorientation
as a Proof of the Stressing of the Femoral Neck 30 Osteotomy .............. . 90
IX
c) Reorientation by Y Osteotomy. . . . .. 100 f) Results of the Abduction (Valgus) Osteotomy
d) Planning and Procedure of Reorientation by (PH) in Cases of Extreme Subluxation of the
Y Osteotomy . . . . . . . . . . .. 102 Femoral Head .............. 236
e) Results of Y Reorientation Osteotomy 104 g) Planning of the Abduction (Valgus)
Osteotomy (PH) in the Presence of Adduction
f) Reorientation of the Pseudarthrosis with
Deformity. . . . . . . . . . . . . .. 238
Reshaping of the Bone by Wedge Resection 116
h) The Effect of Shortening the Leg on the
g) Treatment of Necrosis of the Femoral Head 120
Position of the Femoral Head in the Socket 242
5. Reconstruction of the Femoral Neck by Bone
5. Basic Treatment for Protrusio Acetabuli . . 244
Grafting. . . . . . . . . . . . . . . . . . 124
6. Problems Concerning Indications for PI and
6. Influence of the Position of a Graft in Contact
PH Osteotomy .... 246
with Bone on the Magnitude of the Mechanical
a) No Definite Indication . . . . . . . 246
Stress . . . . . . . . . . . . . . . . . . . 126
b) Alteration of the Indication at Various
Stages of Osteoarthritis . . . . . . . 249
c) Poor Results Following Operations with an
Incorrect Indication .. . . . . . . . 250
C. Osteoarthritis
d) Revision of Poor Results Due to a Wrong
Indication ............ . 255
1. The Pathological Entity and Its Relation to
Mechanics .............. . 129 7. Comparison between the Postoperative Reaction
a) Disturbance of the Biomechanical Equilibrium 129 of Bone Tissue in Osteoarthritis after Arthro
b) The Influence of Articular Cartilage on the plasty and Following Conservative Operations 262
Magnitude and Distribution of Joint
8. The Problem of the Acetabular Arthroplasties 268
Pressure 131
c) The Outline of the Bony Condensation in the
Acetabular Roof (Sourcil) as a Representation
Conclusion 271
of the Diagram of the Compressive Stresses 132
d) The Effect on the Hip Joint of Relatively
Subject Index 273
Excessive Pressure . . . . 136
2. The Task of Basic Treatment 144
3. The Diminution of Articular Pressure by
Reduction of the Load When the Articular
Surfaces Are Congruent (Voss, McMurray). . 144
4. The Reduction of Joint Pressure by Increasing
the Weight-Bearing Area Where There Is
Incongruence of the Joint Contours .... 146
a) The Adduction-Varus Osteotomy (PI) and
the Abduction-Valgus Osteotomy (PH) .. 146
b) The Indications and Planning for the Varus
(Adduction) Osteotomy (PI) and for the
Valgus (Abduction) Osteotomy (PH) 159
c) Results of the Varus (Adduction) Osteotomy
(PI) in the Incipient Stages of Osteoarthritis 165
d) Results of the Varus (Adduction) Osteotomy
(PI) in Advanced Cases of Osteoarthritis
of the Hip .......... 182
e) Results of the Abduction (Valgus)
Osteotomy (PH) ...... . 202
x
I. Theoretical Foundation
A basic treatment of diseases and deformities of the
upper end of the femur which are conditioned by me
chanics, requires that:
1) the physiological stress be known, particularly the in
fluence that divergence of the neck/shaft angle away
from normal has on the loading and stressing in the
upper end of the femur;
2) it be clearly understood how living tissue reacts to the
magnitude and quality of mechanical stress.
The following text is based on new concepts in anat-
0my' some laws of static mechanics, and the theory of
elasticity. As a general rule, these are not, and indeed
cannot be known to the doctor because they are not yet
taught during the Preclinical Period. Therefore, these con
cepts must be analysed and will be demonstrated in the
clearest possible way.
1. Loading and Stressing
One cannot emphasise sufficiently the fundamental
difference between the concept of loading and that of
stressing, since the use of these words as synonyms in the
medical literature has led to many misunderstandings and
incorrect conclusions.
Loading implies the external forces acting on a body.
The term stressing must be restricted to the general
concept of the effect of the external forces on the material,
that is to say, the stresses and strains set up in the material
by loading. It is these and these alone that determine the
effects of the load.
A theoretical example will illustrate the difference in
meaning between loading and stressing (Figs. 1, 2).
1
The three columns (Fig. 1 a to c) have the same carry stressing it provokes. The magnitude of the stress in these
ing capacity; they support the same weight. If the weight columns is shown in diagrams Fig. 2a to d.
is over the centre of the column, its strength is sufficient In these diagrams D indicates compressive stresses
(a). If the weight is displaced slightly laterally, the column and Z tensile stresses. The material of the column is com
bends under the effect of the same load (b). Greater dis pressed on the loaded side. The cross-section of the co
placement of the weight causes the column to break (c). lumns is such that a well-centred load of 20 kp produces
On the other hand, the column can support twice the load pure compressive stresses of 10 kp/cm2 (Fig. 2a). The
if a second weight, equal to the first, is placed on the magnitude of stressing and the danger of collapse are deter
transverse beam at the same distance from the axis of the mined by the maximum stresses in the cross-section of
column but on the opposite side. It acts as a counter the column.
poise (d). These different effects of loading show that the A theoretical example (Fig. 3) will make this easier to
essential feature is not the magnitude of the load but the understand. The rubber band (Fig. 3a) is stressed in ten-
Load:
20kp 20kp 20kp 20 kp 20kp
Fig.1a-d a b c d
Load:
20kp 20kp 20kp 20 kp 20kp
i
I
I
z
z I
I 20kp/cm2
120kp/cm2 200kp/cm2
0 I I
0
I I
Fig.2a-d a b c d
2
sion axially and is uniformly stretched by the weight sus
pended from the middle of its free end. The tension stresses
(1z have the same magnitude throughout the cross-section.
If the weight acts eccentrically (Fig. 3 b), the edge of the
rubber band closer to the attachment of the weight is
more stretched. The tension stresses increase toward this
edge. If the weight is attached still closer to the edge
(Fig. 3c), the band is stretched even further on this side
but is slightly puckered on the opposite side.
Thus, it will be readily understood that it is at the edge
which is most stretched, the one where the maximum
stress is present, that the first tear appears. Complete rup
ture follows immediately because the first tear increases
a b
the stress at the edge. This stress increases more and more
rapidly with progressive tearing because of notch sensi
tivity. Fig.3a-c
2. Effect of Mechanical Stress on the
Skeleton
In consideration of the effect of mechanical stress on
organic tissue, a clear distinction must be drawn between:
1) the immediate effect of mechanical stressing, which is
passive deformation (bones that bend because they are
weakened by rickets are a characteristic example);
2) the reaction of living tissue to mechanical stress. The
reaction in mature bone tissue is fundamentally differ
ent from that in a pluripotent matrix.
3