Andrew John Metcalfe BMedSc MBChB FRCS(Tr&Orth)

405 Pages·2014·8.59 MB·English

K O B D
NEE STEOARTHRITIS IS A ILATERAL ISEASE
Andrew John Metcalfe
BMedSc MBChB FRCS(Tr&Orth)
Presented to the School of Engineering and the School of Medicine at Cardiff
University in partial fulfilment of the requirements for the degree of:
Doctor of Philosophy
2014
Declaration and Statements
Declaration
This work has not been submitted in substance for any other degree or award at
this or any other university or place of learning, nor is being submitted concurrently
in candidature for any degree or other award.
Signed: …………………………………………. (Candidate) Date: 12/10/2014
Statement 1
This thesis is being submitted in partial fulfilment of the requirement for the degree
of PhD.
Signed: …………………………………………. (Candidate) Date: 12/10/2014
Statement 2
This thesis is the result of my own independent work/investigation, except where
otherwise stated. Other sources are acknowledged by explicit references. The views
expressed are my own.
Signed: …………………………………………. (Candidate) Date: 12/10/2014
Statement 3
I hereby give consent for my thesis, if accepted, to be available for photocopying
and for inter-library loan and for the title and summary to be made available to
outside organisations.
Signed: …………………………………………. (Candidate) Date: 12/10/2014
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Acknowledgements
In doing this work, I have been fortunate enough to have had a great amount of
support and assistance from a large number of generous, helpful and talented
people, more than I have space to name individually. There are a few people I must
acknowledge, however, without whom I would have been unable to have put this
work together.
I particularly appreciate the help, support and encouragement that I have received
from my supervisors, Dr Cathy Holt and Dr Rhian Goodfellow, who have managed
to encourage, enthuse and often correct me over a number of years. Their patience
in teaching, the time they have committed, and their willingness to get involved in
topics outside of their comfort area has been a great help.
I am also especially indebted to Dr Caroline Stewart, Dr Neil Postans, Mr Andrew
Roberts and the staff of ORLAU at the Robert Jones and Agnes Hunt Orthopaedic
Hospital in Oswestry. From the very start of this work they have sacrificed large
amounts of time and effort into helping me both with the intellectual development
of ideas throughout this thesis, as well as in the practical delivery of the work itself.
This has often taken up significant amounts of their time but their willingness to
help and their ongoing encouragement has been an inspiration throughout the time
that I have worked on this research.
Dr Carina Thorstensson and Dr Maria Andersson very kindly provided both their
data and repeated help and advice to someone who they had initially only
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communicated with via email and a brief telephone conversation. Their willingness
to let me be involved in their work, and the time they subsequently spent helping
refine the work presented in chapter 3 was greatly appreciated.
The classification work was performed with the help and support of Paul Biggs and
Dr Gemma Whatling, among others, both of whom deserve recognition for their
time spent on, and expertise in, writing code to process the data and then patiently
helping a simple clinician through the complexities of Matlab and the mathematical
processes presented in the thesis. Dr Whatling’s helpful advice and support
throughout the time of this PhD, with advice given on almost every chapter, is also
greatly appreciated.
Dr Emma Blain committed a large amount of time and effort to the mechano-
biology work presented in chapter 6, and worked tirelessly and with endless
patience to help a biology novice through both the academic and practical aspects
of the study, including editing chapter 6. With this study in mind I must also
acknowledge the help of Professor Sam Evans who helped greatly in the set-up and
development of the study as well as producing some of the equipment used. Dr
Joanna Li’s help is also acknowledged in analysing the samples and performing the
finite element modelling which produced a valuable additional facet to the study.
Finally, but most importantly, I have to recognise the sacrifices made and support
given by my wife Helen, my children Ben and Emily, and my family and friends as I
have ruined free time, broken up holidays and spent more time on the computer
then was ever reasonable. Helen has been a great and patient source of support
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over many years and my children continue to brighten and enthuse me no matter
what has happened at work or during a study, and I am deeply indebted to them.
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Abstract
Knee osteoarthritis (OA) is a common cause of pain and disability. Patients often
complain that they overload the other limb when they walk, resulting in disease in
the unaffected knee. However, it is unknown whether this happens or the
mechanism by which it occurs.
Data was analysed from an established longitudinal cohort study to examine the
development of bilateral knee OA. One hundred and forty-three subjects were
examined over a 12 year period with bilateral radiographs. Bilateral knee
osteoarthritis was found to be very common over time, and the majority of
individuals with unilateral knee OA eventually developed bilateral disease.
A gait analysis study was performed on 20 subjects with unilateral knee OA awaiting
arthroplasty surgery and 20 healthy age equivalent controls. Abnormal moments
and muscle co-contractions were observed in the other knee and hips when they
walked due a characteristic slow, cautious, stiff-legged gait pattern. Fifteen subjects
re-attended 12 months following their surgery. Whilst moments returned to normal
in most of the replaced knees, they remained elevated at the contra-lateral side
and co-contraction failed to recover in either knee.
A novel study design is presented to examine the effect of gait-derived loading
waveforms on fresh human osteochondral plugs. By applying mechano-biology
techniques and Finite Element Modelling to fresh human tissue, new observations
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can be made about the relationship between in-vivo loading and cartilage
mechano-biology.
A characteristic gait pattern was observed in knee OA which is not simply antalgic
but tends towards symmetry, with an increase in joint loading bilaterally. The
observed gait behaviour does not resolve, despite arthroplasty of the affected joint.
This would be expected to contribute to the development of disease in an
inherently vulnerable joint. Additional training may have a role to play in restoring
normal biomechanics and protecting the other knee from disease.
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Table of Contents
DECLARATION AND STATEMENTS I
ACKNOWLEDGEMENTS II
ABSTRACT V
TABLE OF CONTENTS VII
LIST OF ABBREVIATIONS XIII
CHAPTER 1. INTRODUCTION 1
CHAPTER 2. BACKGROUND AND LITERATURE REVIEW 6
2.1OSTEOARTHRITIS THE DISEASE 7
2.1.1 History of osteoarthritis 7
2.1.2 Definition of Osteoarthritis 9
2.1.3 Epidemiology of OA: Prevalence and Economic Impact 10
2.1.4 Pathophysiology of osteoarthritis 12
2.1.5 Risk factors for OA development and progression 19
2.1.6 Classification of OA 22
2.1.7 Measuring Pain and Function in OA 25
2.1.8 Multiple Joint OA 28
2.1.8 Treatments for OA 33
2.1.9 Conservative Treatments 33
2.1.10 Surgical Treatments for OA 35
2.2OVERVIEW OF GAIT ANALYSIS 39
2.2.1 Principles of modern gait analysis 39
2.2.2 Data collection in gait analysis 42
2.2.3 Conventions in describing position, motion and forces 46
2.2.4 Principles of data processing for gait analysis 50
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2.2.5 Sources of Error 53
2.2.6 Overall Reliability of Gait Analysis 59
2.2.7 Electromyography (EMG) 60
2.3GAIT ANALYSIS IN OA 63
2.3.1 Gait changes in knee OA 63
2.3.2 Gait changes in Total Knee Replacement 65
2.3.3 The Knee Adduction Moment 66
2.3.4 The Hip Adduction Moment 71
2.3.5 Muscular Co-Contraction 73
2.3.6 Loading of Unaffected joints in Patients with Knee OA – the Same Side 76
2.3.7 Loading of Unaffected joints in Patients with Knee OA – the Other Side 77
2.4AIMS AND OBJECTIVES 81
CHAPTER 3. IS KNEE OA A SYMMETRICAL DISEASE? ANALYSIS OF A 12 YEAR PROSPECTIVE
COHORT. 82
3.1INTRODUCTION 83
3.2METHODS 84
3.2.1 Development of the study 84
3.2.2 Description of the cohort study 85
3.2.3 Analysis of the data 88
3.3RESULTS 90
3.3DISCUSSION 98
3.3.1 Overview of findings 98
3.3.2 Limitations of the study 99
3.3.4 Implications and Conclusion 100
CHAPTER 4. ABNORMAL LOADING OF THE MAJOR WEIGHT BEARING JOINTS IN KNEE OA 103
4.1INTRODUCTION 104
4.2MATERIALS AND METHODS 107
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4.2.1 Study development and management 107
4.2.2 Recruitment and patient selection 109
4.2.3 Gait Analysis Protocol 115
4.2.4 Data Processing 119
4.2.5 Development of a measurement for dynamic limb alignment 124
4.2.6 Statistical Analysis 138
4.2.7 Examination of component parts of frontal plane moments 140
4.2.8 Exploration of the effect of gait speed in normal individuals 142
4.3RESULTS 145
4.3.1 Demographics 145
4.3.2 Gait Analysis Findings 146
4.3.3 Co-contraction findings 155
4.3.4 Findings from the dynamic alignment measure 158
4.3.4 Exploration of Moments 164
4.3.5 The relationship between gait speed and moments 170
4.4DISCUSSION 175
4.4.1 Overview 175
4.4.2 Kinetics 176
4.4.3 Co-contraction 182
4.4.4 Dynamic Alignment 185
4.4.5 Weaknesses of the study 188
4.5CONCLUSIONS AND FURTHER INVESTIGATION 191
CHAPTER 5. BIOMECHANICS OF THE AFFECTED AND UNAFFECTED JOINTS FOLLOWING KNEE
REPLACEMENT 193
5.1INTRODUCTION 194
5.1.1 Overview 194
5.1.2 Analysis of complex gait data sets 194
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