Дисертації з теми "Chrinic low back pain"

Malgré les progrès réalisés par le système de santé, la lombalgie chronique reste la principale cause d'invalidité. Le déficit d'extensibilité des muscles ischio-jambiers (MIJ), combiné à un déficit de contrôle neuromusculaire, contribue à l'invalidité dans la lombalgie chronique. Dans ce travail, nous décrivons d'abord les mécanismes de la douleur, le modèle biopsychosocial et la biomécanique, en se concentrant sur les déficits d'extensibilité des MIJ. Ensuite, nous estimons les propriétés métrologiques des mesures de l'extension active du genou, Active Knee Extension (AKE), et de la levée de jambe tendue, Straight Leg Raise (SLR) obtenues à l'aide d'un nouvel inclinomètre éléctronique chez les patients souffrant d'une lombalgie chronique. Cette analyse a été effectuée sur les 90 patients inclus dans l'étude EFIM1. La reproductibilité intra-évaluateur pour AKE et SLR s'est révélée excellente, avec un coefficient de corrélation intraclasse, Intraclass Correlation Coefficient (ICC) supérieur à 0,9. Les valeurs de différence minimale détectable, Minimal Detectable Change (MDC95) ont été de 9 à 11° pour AKE et de 7 à 10° pour SLR. Des corrélations modérées à fortes, ont également été trouvées entre AKE, SLR et la distance doigt-sol, Fingertip-to-Floor (FTF), ce qui confirme la validité de construit de nos mesures. L'étape suivante concernait l'évaluation de l'effet immédiat de l'étirement passif des MIJ, ainsi que l'analyse de l'impact des facteurs psychosociaux sur le changement résultant de l'étirement (étude EFIM1). Les mesures répétées de l'extensibilité des MIJ (AKE, SLR, FTF) ont été effectuées sur 90 patients atteints de lombalgie chronique avant et immédiatement après l'intervention. Celle-ci consistait en une minute d'étirement passif des MIJ réalisée de manière bilatérale par un kinésithérapeute. Les facteurs psychosociaux ont été évalués avant l'intervention grâce aux questionnaires Fear-Avoidance Belief Questionnaire (FABQ) et Hospital Anxiety and Depression Scale (HADS). L'extensibilité des MIJ s'est améliorée de manière significative après l'étirement; la différence moyenne de l'AKE était de 4° (IC à 95 % : 2,4 à 5,1° ; p < 0,001), la différence moyenne de la SLR était de 7° (IC à 95 % : 5,5 à 8,6°, p < 0,001), la différence moyenne de FTF était de 2 cm (IC à 95 % : 1,7 à 3,0cm, p < 0,001). Aucune corrélation n'a été trouvée entre l'amélioration d'extensibilité des MIJ et les scores des questionnaires FABQ ou HADS (p > 0,05). L'étirement passif des MIJ a entraîné une amélioration immédiate et statistiquement significative de l'extensibilité des MIJ chez les personnes atteintes de lombalgie chronique. Cependant, seul le changement d'amplitude passive de la SLR semble avoir une importance clinique. Cela suggère que le système neuromusculaire nécessite une stimulation active pour générer un mouvement actif dans l'amplitude de mouvement passive nouvellement acquise. Par conséquent, nous présentons un nouveau protocole d'étude randomisée contrôlée, EFIM2 pour vérifier si la combinaison d'étirements actifs et passifs est plus efficace que l'étirement passif seul pour améliorer la flexibilité active chez les patients souffrant d'une lombalgie chronique
Progress in healthcare management increased life expectancy globally but disabling consequences of diseases remain the major problem. Despite the progress that has been made in healthcare management, chronic low back pain (CLBP) remains the leading cause of disability. The deficit in hamstring muscles (HM) flexibility, combined with a deficit in neuromuscular control, contributes to disability in CLBP. In this work, we first describe the context that links pain mechanisms, the biopsychosocial model, and biomechanics, with a specific focus on HM flexibility deficits. Then, we estimate the measurement properties of the Active Knee Extension (AKE) and Straight Leg Raise (SLR) measures taken with a new digital inclinometer in CLBP patients. Intrarater reproducibility was found to be acceptable, with a Minimal Detectable Change of 9-11° for AKE and 7-10° for SLR. Following that, we conducted the EFIM1 study to evaluate the immediate effect of passive hamstring (HM) stretching on flexibility and to analyze the impact of psychosocial factors on change following HM stretching in 90 CLBP patients. Hamstrings flexibility improved significantly after stretching; AKE mean difference was 4° (95%CI, 2.4 to 5.1; p<0.001); SLR mean difference was 7° (95%CI, 5.5 to 8.6, p<0.001), Fingertips-to-Floor mean difference was 2 cm (95%CI, 1.7 to 3.0, p<0.001). No correlation was found between improvement in any of the HM flexibility measurements and Fear-Avoidance Belief Questionnaire (FABQ) or Hospital Anxiety and Depression Scale (HADS) scores (p>0.05). Additional group-based analysis showed that the Positive Responders and Non-Responders groups were similar in demographic and clinical characteristics, except for lower Body Mass Index (BMI) values within the Positive Responders group. Passive HM stretching induced an immediate, statistically significant improvement in HM flexibility in people with CLBP. However, only the change in SLR amplitude is likely to be of clinical importance. Psychosocial factors were not related to observed improvements in flexibility. This suggests that the neuromuscular system needs active stimulation to generate active movement in the newly acquired passive range of motion (ROM). Therefore, in response to this conclusion we present a new study protocol, EFIM2. From the patient's perspective, the ultimate goal is to achieve an important improvement in active, pain-free ROM. However, passive stretching did not yield satisfactory improvements in active flexibility. This is why we propose a combination of passive and active stretching exercises, with the expectation that it facilitates improvements in both passive and active ROM. To test our hypothesis that combining active and passive stretching is more effective than passive stretching alone in improving active flexibility, we present a randomized controlled study, EFIM2

The cause of low back pain in populations of professional drivers is uncertain. A literature review revealed factors that seem to be associated with low back pain (e.g. physical factors: exposure to whole body-vibration, prolonged sitting posture, frequent lifting, pushing and pulling, lack of physical fitness; psychosocial factors: job satisfaction or stress; individual factors: age, gender, anthropometrics, tobacco, alcohol consumption, etc.). This thesis investigates the occurrence of back pain in professional car drivers – a group found to be not focussed upon in previous epidemiological studies. The thesis seeks to advance understanding of response relationships between risk factors and low back pain in populations of car drivers (209 taxi drivers and 365 police drivers) and 485 non-drivers. A longitudinal study with cross-sectional baseline combined with field measurement of driving in selected vehicles was performed to investigate the occurrence of musculoskeletal problems (mainly low back pain) and the relationship between risk factors and low back pain experienced for at least one day during the past 12 months in the two populations of professional drivers (taxi drivers and police drivers) and professional non-drivers. The cross-sectional baseline of the longitudinal study revealed that 45% (38.3-51.7%) of taxi drivers, 53% (48-58.6%)of police drivers and 46% (41-50.1%) of police non-drivers reported low back pain for at least one day during the past 12-months (p = 0.09). The prevalence of low back pain in the non-driving population of police employees fell within prevalence range reported by professional car drivers in this study and in previous epidemiological studies. The cross-sectional study revealed risk factors associated with the prevalence of low back pain (i.e., stature, previous physical demands, increased psychosomatic distress, daily and cumulative driving in taxi drivers; age, lifting, bending, increase psychosomatic distress in police drivers; stature, bending, increased psychosomatic distress in police non-drivers). Measurements of whole-body vibration in selected taxi and police vehicles revealed frequencyweighted accelerations in the dominant vibration direction (i.e., z-axis) to be 0.47 ms-2 r.m.s. in taxi vehicles and 0.58 ms-2 r.m.s. in police vehicles. A study of cumulative exposure to whole-body vibration in a group of taxi drivers pointed to a possible overestimation of their self-estimated duration of vibration exposure by 31% on average. The longitudinal study revealed a lower incidence of low back pain in taxi drivers than in both police drivers and police non-drivers (p = 0.02). The difference might be attributed to a different approach to low back pain in taxi drivers who lose income if unable to work. An alternative explanation for increased low back pain among police employees could be that taxi drivers with low back pain leave their profession and were excluded from the follow-up study – a healthy worker effect. The longitudinal study revealed that increased psychosomatic distress was a risk factor associated with the development of new episodes of low back pain in all three of the studied populations (i.e. taxi drivers and police drivers and non-drivers). In police drivers, increased daily duration of driving was a risk factor for the development of low back pain. Although the results point to increased incidence of low back pain with increasing duration of daily driving, non-drivers were at a similar risk of developing of low back pain. Plausible explanations for this finding include ergonomic factors that were present for both the drivers and the non-drivers (e.g., the duration of sitting or duration in a constrained posture) and the presence of other risk factors not investigated in the study but associated with increased incidence of low back pain in non-drivers.

Chronic low back pain (CLBP) causes ongoing pain, disability and psychological suffering, at a huge personal and socio-economic cost. CLBP is a heterogeneous condition and its mechanisms are poorly understood. Characterisation and classification of low back pain (LBP) is controversial, there is disagreement on the characterisation and diagnosis of neuropathic low back pain (NuLBP) in relation to mechanical LBP (MLBP). Diagnostic uncertainty is coupled with poor clinical outcomes for treatment. There is therefore an urgent need to develop more effective assessment strategies to identify and better differentiate NuLBP from MLBP in order to facilitate a better understanding of underlying mechanisms and more successful treatments. The primary aim of this study was to establish clinical profiles of CLBP, in particular, differences between MLBP and NuLBP using Questionnairebased behavioural evaluation and sensory testing, structural neuroimaging (voxel based morphometry) and functional neuroimaging (arterial spin labelling). Significant differences were identified between CLBP patients and healthy controls and between NuLBP and MLBP patients in multiple behavioural domains measuring pain, function and psychological well-being. Significant differences were demonstrated in CLBP patients compared to controls in both tactile threshold discrimination and two-point discrimination and between NuLBP and MLBP in tactile threshold discrimination. Functional and structural neuroimaging showed significant differences between all groups in widespread brain regions involved in the evaluation of decision making and planning, mood and emotion, modulation of pain and representation of body schema. This study has demonstrated the ability to characterise CLBP using a battery of behavioural, examination and functional and structural neuroimaging methodologies and has been able to differentiate between CLBP patients and controls and importantly, between NuLBP and MLBP patients. This work demonstrates the impact of CLBP across sensory-discriminative, affectivemotivational and cognitive-evaluative dimensions of the pain experience and shows the increased impact and burden on those who suffer with NuLBP compared to MLBP.

This thesis is organised into eight chapters. It is written so that each chapter can be read independently and has its own reference list. Four of the eight chapters have been published in peer-reviewed scientific journals. The University of Sydney permits the published papers that arose during the candidature to be included in the thesis. Chapter One introduces the problem of overdiagnosis in low back pain, and presents gaps in knowledge, which this thesis aimed to address. Chapter Two is a systematic review of 69 qualitative studies on clinician and patient beliefs about diagnostic imaging for low back pain. This manuscript is presented as published in British Medical Journal Open. Chapter Three highlights challenges in managing low back pain in low- and middle-income countries, using Nepal as an example. This manuscript is presented as published in the Journal of Global Health. Chapter Four is a randomised controlled trial of 418 members of the public testing the effect of information format on intention and beliefs regarding diagnostic imaging for non-specific low back pain. This manuscript is presented as published in the Patient Education and Counselling. Chapter Five is a focus group study of community response to a public health campaign aimed at reducing unnecessary diagnostic imaging for low back pain. This manuscript is presented as published in the Health Expectations. Chapter Six is a controlled experimental study with BABA design to determine the effect of a waiting room communication strategy to raise awareness of potential harms of unnecessary imaging on lumbar imaging rates in the Emergency Department. This manuscript is presented as submitted to Annals of Behavioural Medicine. Chapter Seven is a retrospective analysis of electronic medical record data on care for low back pain in three emergency departments in Sydney before and during the COVID-19 pandemic. This manuscript is presented as submitted to The Spine Journal. Chapter Eight summarises the main findings of this thesis and makes recommendations for future research and practice.

Acute low back pain is a commonly occurring symptom that can impact considerably upon a person's life. It is poorly defined, difficult to classify and challenging to measure. However, due to the high prevalence rates of the symptom, cited in the epidemiological literature, and the costs incurred by individuals, health services and society in general, it is vital that clients are encouraged to take more responsibility for their health. This thesis is concerned with perceptions of control in people with acute low back pain. It is about how they respond to this symptom and the way it impacts upon their lives. The underpinning literature is drawn from both medical and social science research, as the work crosses faculty boundaries. Problems are addressed from a physiotherapeutic and social science perspective, as links are formed between the different disciplines. From this literature, a significant theoretical development was the creation of a framework, which enabled the systematic review of existing outcome measures. A number of instruments, relevant to clients with acute low back pain, were reviewed using this framework, for the dimensions of control, function, pain and anxiety. The findings were used to inform the selection of outcome measures in this research. Four studies were then undertaken, all linked to studying clients with acute low back pain. The first study was a survey of general practitioners in Southampton and the New Forest, which identified their strategies for managing clients with acute low back pain. The second study focused on clients' experiences and was a randomized controlled trial, which tested the effectiveness of an information leaflet, designed to encourage clients to take more responsibility for their own health. The third study primarily focused on clients' perceptions of control over time, addressing the question of how these perceptions change during a one-year period. Finally, since recruitment of clients by their doctors was problematic throughout this research, a follow-up survey was undertaken with these health professionals to establish the reasons for this. The results of these studies are used to discuss the importance of clients' perceptions of control and the implications for clinical practice.

Thesis (Ph. D.)--University of Sydney, 2009.
Title from title screen (viewed Aug. 11, 2009) Includes tables and questionnaires. Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Public Health, Faculty of Medicine. Includes bibliographical references. Also available in print form.

Abstract Low back pain is a significant public health problem in many countries of the world being one of the major causes of work absence and disability. Although the outlook for evidence-based management of low back pain has greatly improved over the past decades, many questions remain. Questions related to treatment options, underlying mechanisms of treatment effects and optimal assessment of low back pain have yet to be fully addressed by researchers. The broad aim of this thesis therefore was to contribute to a better understanding of the contemporary management of low back pain by performing studies in these key research areas. Most clinical practice guidelines recommend exercise as an effective treatment option for chronic low back pain. However the evidence for this recommendation comes from trials that are not placebo-controlled and so this may potentially provide biased estimates of the effects of exercise. Therefore a randomised controlled trial testing the effect of motor control exercise versus placebo in patients with chronic low back pain was conducted. Chapters 2 and 3 describe the trial protocol and the report of the trial respectively. A total of 154 patients with chronic low back pain were randomised to receive a motor control exercise program, or placebo (i.e. detuned short-wave therapy and detuned ultrasound therapy). Primary outcomes were pain, function, and the patient’s global impression of recovery measured at 2 months. The exercise intervention improved function and patient’s global impression of recovery, but not pain, at 2 months. The mean effect of exercise on function was 1.1 points (95%CI, 0.3 to 1.8), the mean effect on global impression of recovery was 1.5 points (95%CI, 0.4 to 2.5) and the mean effect on pain was 0.9 points (95%CI, - 0.01 to 1.8), all measured on 11 point scales. Secondary outcomes also favoured motor control exercise. This is the first study ever to demonstrate that motor control exercise is better than placebo for patients with chronic low back pain. Most of the treatment effects were maintained at 6 and 12 months follow-up. These results suggest that this intervention should be considered for patients with chronic low back pain in order to improve disability, function, and global impression of recovery, and to improve pain intensity in the long term, but not in the short term. Rehabilitative ultrasound imaging (RUSI) has been increasingly used by physiotherapists in order to identify impairments in motor control as well as to monitor progress of patients with low back pain. As with any other clinical measure it is important to know how reproducible the RUSI measures are, and although there are some reproducibility studies in the literature, no systematic review on this topic has been conducted. Therefore a systematic review was performed with the objective of assessing the reproducibility studies of RUSI for abdominal wall muscles (Chapter 4). Eligible studies were indentified via searches in CINAHL, EMBASE and MEDLINE with citation tracking via the Web of Science Index. A total of 21 studies were included. Due to heterogeneity of the studies’ designs, pooling the data for a meta-analysis was not possible. RUSI measures of thickness of abdominal wall muscles were found to be reliable. Few studies analysed the reliability for the measurement of thickness changes (reflecting the muscle activity) finding good to poor results. Evidence for the reproducibility of the difference in thickness changes over time (necessary to evaluate improvements in muscle activity with treatment) was not available. A limitation of the existing literature is that studies typically had suboptimal designs and analysis. The current evidence for the reproducibility of RUSI for measuring abdominal muscle activity is mainly based upon studies with suboptimal designs that included mostly healthy subjects, making generalisability to clinical settings uncertain. Some questions about the reproducibility of RUSI measures of abdominal wall muscles are still unanswered; this is mainly due to design issues, such as inadequate statistics, inadequate sampling and lack of control of sources of bias (e.g. blinding and absence of controlling for ordering effects). In addition the clinically important questions about the reproducibility of thickness changes (reflecting the muscle activity) and differences in thickness changes over time (reflecting the improvement or deterioration of muscle activity) have not been adequately investigated. Therefore a reproducibility study that aimed to answer these questions was performed (Chapter 5). Thirty-five patients seeking care for chronic low back pain participated in this study. RUSI measures were taken at baseline and eight weeks post-baseline. Replicate measures of thickness, thickness changes and differences in thickness changes over time were analysed. The reproducibility of static images (thickness) was excellent (ICC2,1 = 0.97, 95%CI = 0.96-0.97, Standard Error of the Measurement (SEM) = 0.04cm, Smallest Detectable Change (SDC) = 0.11cm), the reproducibility of thickness changes was moderate (ICC2,1 = 0.72, 95%CI 0.65-0.76 SEM = 15%, SDC 41%), while the reproducibility of differences in thickness changes over time was poor. Improvements in the test protocol should be undertaken in order to enhance the reproducibility of RUSI measures, especially for differences in thickness chang over time. Self-report outcome measures (questionnaires) are widely used by health care providers for measuring patient’s health status or treatment outcomes. Most of the questionnaires related to low back pain were developed in English and therefore their usefulness in non-English speaking countries is considerably limited. Cross-cultural adaptation and clinimetric testing are possibly the most efficient methods for solving this problem. Although there are many publications on the topic, a simple guide on how to perform a cross-cultural adaptation and clinimetric testing was not available. Therefore a “clinician-friendly” narrative review for Brazilian physical therapists (Chapter 6) was written. This review aimed firstly to explain the concepts and the relevance of cross-cultural adaptation and clinimetrics testing, secondly to summarise the current guidelines on the topic, thirdly to provide advice on how to choose a relevant questionnaire and finally how to evaluate the quality of an adapted questionnaire. Some examples of cross-cultural adaptations and clinimetrics testing of relevant low back pain questionnaires in the Brazilian-Portuguese language were also provided. Although the number of international versions of low back questionnaires is growing, to date it is unclear which questionnaires have been cross-culturally adapted and into which specific language. To answer these questions a systematic review was conducted in order to describe the available cross-cultural adaptations of low back pain self-report outcome measures and the clinimetric testing that has occurred for each adaptation (Chapter 7). Searches were performed in MEDLINE, EMBASE, CINALH and LILACS; these searches were supplemented with information from experts in the field of low back pain from 27 different countries to ensure that the results were comprehensive. Sixty-one adaptations were identified. While there are a large number of low back pain questionnaires available, very few have been adapted into other languages, particularly commonly spoken languages such as Mandarin, Hindi and Portuguese. The quality and comprehensiveness of clinimetric testing varied considerably, with the evaluation of reliability and construct validity most common. Further cross-cultural adaptation and clinimetric studies are clearly needed and special consideration must be given to study designs for clinimetric testing. The final aim of this thesis was to cross-culturally adapt self-report instruments relevant to the management of low back pain in Brazil. This was achieved by two independent studies. The first study (Chapter 8) aimed to cross-culturally adapt the Functional Rating Index (FRI) into Brazilian-Portuguese and to test the clinimetric properties of the FRI and also of an existing Brazilian-Portuguese version of the Roland Morris Disability Questionnaire (RMDQ) which was not fully evaluated in the original study. Both instruments were tested for internal consistency, reliability, construct validity, ceiling and floor effects and internal responsiveness in 140 chronic low back patients presenting for physiotherapy treatment in Brazil. Both instruments were considered reliable and valid for the measurement of disability in Brazilian-Portuguese speakers with low back pain, no ceiling or floor effects were detected, but the internal responsiveness of both instruments was considered small. The second study (Chapter 9) aimed to cross-culturally adapt the Patient-Specific Functional Scale (PSFS) and to perform a head-to-head comparison of the clinimetric properties of the PSFS, RMDQ and FRI. All instruments were tested for internal consistency, reliability, construct validity, ceiling and floor effects, internal and external responsiveness in 99 acute low back patients presenting for physiotherapy treatment in Brazil. In order to fully test the construct validity and external responsiveness, it was necessary to cross-culturally adapt the Pain Numerical Rating Scale and the Global Perceived Effect Scale. The results of this study demonstrate that the Brazilian-Portuguese versions of the RMDQ, FRI and PSFS have similar clinimetric properties to each other and to the original English versions; however the PSFS was the most responsive instrument. The results from the studies in Chapters 8 and 9 will benefit the understanding of low back pain by enabling international comparisons between studies conducted in Brazil and English speaking countries. In addition it will encourage researchers to include Brazilian- Portuguese speakers in their future clinical trials. Overall, the studies included in this thesis have provided an important contribution to the contemporary management of low back pain. Firstly the use of motor control exercise could be considered for patients with chronic low back pain as it produces improvements in global impression of recovery, function, disability and pain. Secondly RUSI measures of abdominal wall muscles in patients with low back pain were considered reproducible for the measurement of muscle activity, but not as an outcome measure to detect improvement/deterioration of muscle activity over the course of treatment. Thirdly just a few high-quality cross-cultural adaptations and clinimetrics testing for self-report outcome measures relevant to the management of low back pain are available, and clearly more studies in this area are needed. Finally the Brazilian-Portuguese versions of the Functional Rating Index, the Roland Morris Disability Questionnaire and the Patient-Specific Functional Scale have acceptable clinimetric properties and could be used in clinical practice as well as in research studies in Brazil.

PhD
Abstract Low back pain is a significant public health problem in many countries of the world being one of the major causes of work absence and disability. Although the outlook for evidence-based management of low back pain has greatly improved over the past decades, many questions remain. Questions related to treatment options, underlying mechanisms of treatment effects and optimal assessment of low back pain have yet to be fully addressed by researchers. The broad aim of this thesis therefore was to contribute to a better understanding of the contemporary management of low back pain by performing studies in these key research areas. Most clinical practice guidelines recommend exercise as an effective treatment option for chronic low back pain. However the evidence for this recommendation comes from trials that are not placebo-controlled and so this may potentially provide biased estimates of the effects of exercise. Therefore a randomised controlled trial testing the effect of motor control exercise versus placebo in patients with chronic low back pain was conducted. Chapters 2 and 3 describe the trial protocol and the report of the trial respectively. A total of 154 patients with chronic low back pain were randomised to receive a motor control exercise program, or placebo (i.e. detuned short-wave therapy and detuned ultrasound therapy). Primary outcomes were pain, function, and the patient’s global impression of recovery measured at 2 months. The exercise intervention improved function and patient’s global impression of recovery, but not pain, at 2 months. The mean effect of exercise on function was 1.1 points (95%CI, 0.3 to 1.8), the mean effect on global impression of recovery was 1.5 points (95%CI, 0.4 to 2.5) and the mean effect on pain was 0.9 points (95%CI, - 0.01 to 1.8), all measured on 11 point scales. Secondary outcomes also favoured motor control exercise. This is the first study ever to demonstrate that motor control exercise is better than placebo for patients with chronic low back pain. Most of the treatment effects were maintained at 6 and 12 months follow-up. These results suggest that this intervention should be considered for patients with chronic low back pain in order to improve disability, function, and global impression of recovery, and to improve pain intensity in the long term, but not in the short term. Rehabilitative ultrasound imaging (RUSI) has been increasingly used by physiotherapists in order to identify impairments in motor control as well as to monitor progress of patients with low back pain. As with any other clinical measure it is important to know how reproducible the RUSI measures are, and although there are some reproducibility studies in the literature, no systematic review on this topic has been conducted. Therefore a systematic review was performed with the objective of assessing the reproducibility studies of RUSI for abdominal wall muscles (Chapter 4). Eligible studies were indentified via searches in CINAHL, EMBASE and MEDLINE with citation tracking via the Web of Science Index. A total of 21 studies were included. Due to heterogeneity of the studies’ designs, pooling the data for a meta-analysis was not possible. RUSI measures of thickness of abdominal wall muscles were found to be reliable. Few studies analysed the reliability for the measurement of thickness changes (reflecting the muscle activity) finding good to poor results. Evidence for the reproducibility of the difference in thickness changes over time (necessary to evaluate improvements in muscle activity with treatment) was not available. A limitation of the existing literature is that studies typically had suboptimal designs and analysis. The current evidence for the reproducibility of RUSI for measuring abdominal muscle activity is mainly based upon studies with suboptimal designs that included mostly healthy subjects, making generalisability to clinical settings uncertain. Some questions about the reproducibility of RUSI measures of abdominal wall muscles are still unanswered; this is mainly due to design issues, such as inadequate statistics, inadequate sampling and lack of control of sources of bias (e.g. blinding and absence of controlling for ordering effects). In addition the clinically important questions about the reproducibility of thickness changes (reflecting the muscle activity) and differences in thickness changes over time (reflecting the improvement or deterioration of muscle activity) have not been adequately investigated. Therefore a reproducibility study that aimed to answer these questions was performed (Chapter 5). Thirty-five patients seeking care for chronic low back pain participated in this study. RUSI measures were taken at baseline and eight weeks post-baseline. Replicate measures of thickness, thickness changes and differences in thickness changes over time were analysed. The reproducibility of static images (thickness) was excellent (ICC2,1 = 0.97, 95%CI = 0.96-0.97, Standard Error of the Measurement (SEM) = 0.04cm, Smallest Detectable Change (SDC) = 0.11cm), the reproducibility of thickness changes was moderate (ICC2,1 = 0.72, 95%CI 0.65-0.76 SEM = 15%, SDC 41%), while the reproducibility of differences in thickness changes over time was poor. Improvements in the test protocol should be undertaken in order to enhance the reproducibility of RUSI measures, especially for differences in thickness chang over time. Self-report outcome measures (questionnaires) are widely used by health care providers for measuring patient’s health status or treatment outcomes. Most of the questionnaires related to low back pain were developed in English and therefore their usefulness in non-English speaking countries is considerably limited. Cross-cultural adaptation and clinimetric testing are possibly the most efficient methods for solving this problem. Although there are many publications on the topic, a simple guide on how to perform a cross-cultural adaptation and clinimetric testing was not available. Therefore a “clinician-friendly” narrative review for Brazilian physical therapists (Chapter 6) was written. This review aimed firstly to explain the concepts and the relevance of cross-cultural adaptation and clinimetrics testing, secondly to summarise the current guidelines on the topic, thirdly to provide advice on how to choose a relevant questionnaire and finally how to evaluate the quality of an adapted questionnaire. Some examples of cross-cultural adaptations and clinimetrics testing of relevant low back pain questionnaires in the Brazilian-Portuguese language were also provided. Although the number of international versions of low back questionnaires is growing, to date it is unclear which questionnaires have been cross-culturally adapted and into which specific language. To answer these questions a systematic review was conducted in order to describe the available cross-cultural adaptations of low back pain self-report outcome measures and the clinimetric testing that has occurred for each adaptation (Chapter 7). Searches were performed in MEDLINE, EMBASE, CINALH and LILACS; these searches were supplemented with information from experts in the field of low back pain from 27 different countries to ensure that the results were comprehensive. Sixty-one adaptations were identified. While there are a large number of low back pain questionnaires available, very few have been adapted into other languages, particularly commonly spoken languages such as Mandarin, Hindi and Portuguese. The quality and comprehensiveness of clinimetric testing varied considerably, with the evaluation of reliability and construct validity most common. Further cross-cultural adaptation and clinimetric studies are clearly needed and special consideration must be given to study designs for clinimetric testing. The final aim of this thesis was to cross-culturally adapt self-report instruments relevant to the management of low back pain in Brazil. This was achieved by two independent studies. The first study (Chapter 8) aimed to cross-culturally adapt the Functional Rating Index (FRI) into Brazilian-Portuguese and to test the clinimetric properties of the FRI and also of an existing Brazilian-Portuguese version of the Roland Morris Disability Questionnaire (RMDQ) which was not fully evaluated in the original study. Both instruments were tested for internal consistency, reliability, construct validity, ceiling and floor effects and internal responsiveness in 140 chronic low back patients presenting for physiotherapy treatment in Brazil. Both instruments were considered reliable and valid for the measurement of disability in Brazilian-Portuguese speakers with low back pain, no ceiling or floor effects were detected, but the internal responsiveness of both instruments was considered small. The second study (Chapter 9) aimed to cross-culturally adapt the Patient-Specific Functional Scale (PSFS) and to perform a head-to-head comparison of the clinimetric properties of the PSFS, RMDQ and FRI. All instruments were tested for internal consistency, reliability, construct validity, ceiling and floor effects, internal and external responsiveness in 99 acute low back patients presenting for physiotherapy treatment in Brazil. In order to fully test the construct validity and external responsiveness, it was necessary to cross-culturally adapt the Pain Numerical Rating Scale and the Global Perceived Effect Scale. The results of this study demonstrate that the Brazilian-Portuguese versions of the RMDQ, FRI and PSFS have similar clinimetric properties to each other and to the original English versions; however the PSFS was the most responsive instrument. The results from the studies in Chapters 8 and 9 will benefit the understanding of low back pain by enabling international comparisons between studies conducted in Brazil and English speaking countries. In addition it will encourage researchers to include Brazilian- Portuguese speakers in their future clinical trials. Overall, the studies included in this thesis have provided an important contribution to the contemporary management of low back pain. Firstly the use of motor control exercise could be considered for patients with chronic low back pain as it produces improvements in global impression of recovery, function, disability and pain. Secondly RUSI measures of abdominal wall muscles in patients with low back pain were considered reproducible for the measurement of muscle activity, but not as an outcome measure to detect improvement/deterioration of muscle activity over the course of treatment. Thirdly just a few high-quality cross-cultural adaptations and clinimetrics testing for self-report outcome measures relevant to the management of low back pain are available, and clearly more studies in this area are needed. Finally the Brazilian-Portuguese versions of the Functional Rating Index, the Roland Morris Disability Questionnaire and the Patient-Specific Functional Scale have acceptable clinimetric properties and could be used in clinical practice as well as in research studies in Brazil.

This thesis reports a series of studies investigating the use of one form of spinal manipulative therapy: mobilisation treatment for low back pain. A number of treatment dose parameters such as ‘force characteristics’, ‘spinal level treated’ and ‘mobilisation technique used’ have been investigated in order to gain a better understanding of mobilisation treatment. The first study describes the development and evaluation of an instrumented plinth (called the Sydney Instrumented Plinth or SIP) capable of measuring the forces used during manual treatment (Chapter 2). The SIP was found to be highly reliable in measuring forces in three directions. Importantly, the SIP measures the force-time data without interfering with the normal treatment protocol and is portable enough to permit data collection in treatment clinics.

The 42 peer-reviewed journal publications in this DMedSc thesis are a subset of Prof Chris Maher’s 574 publications for the period 1988 – January 2018. The information in the published work is derived from his research and scholarship in this period. The publications are grouped in the following eight chapters: introduction to low back pain, triggers for low back pain, prevention, screening for serious pathology, prognosis, pharmacological management, non-pharmacological management and evidence-practice gaps.

Background Chronic low back pain (LBP) is a common health problem, with a large potential for primary prevention. Health utilities (HU) reflect which proportion of their expected remaining life time individuals would hypothetically trade to be alleviated of a health condition of interest. A value of 0 means “prefer to die immediately”, a value of 1 means “not willing to trade any life time”. The aim of this cross-sectional study was to assess HU for LBP patients and for healthy participants and to examine whether HU for LBP are useful indicators to substantiate preventive and therapeutic decision making. Methods Healthy participants (n = 126) and LBP patients (n = 32) were recruited mainly among the employees of a tertiary care hospital in Germany. Standardized LBP scenarios were presented to all participants and HU values were assessed using the time-trade-off method. Results Median HU for LBP were 0.90 (IQR 0.31) for participants and 0.93 (IQR 0.10) for LBP patients. Measurements were consistent across illness severity ratings with HU and with a visual analogue scale (VAS); in the healthy sample the intraclass correlation coefficient (ICC) was 0.61 (95% CI 0.23–1.00, F(1125) = 190, p < .001), in the patient sample the ICC was 0.66 (95% CI = 0.24–1.00, F(1,31) = 62, p < .001). 8% of participants reported HU of 1. There was no statistically significant relation between HU and age, income, or gender. Conclusion On average, participants chose a 7 to 10% shorter life expectancy to avoid LBP, but almost 1 in 10 participants were not willing to trade any life years. The results indicate a certain stability of HU due to the comparability of HU ratings across patients and healthy participants, the measurement consistency when comparing VAS and HU ratings, and the lack of association between demographic variables and HU. This underlines the usefulness of HU for measuring illness severity in comparative health economics evaluations of preventive and therapeutic measures that address chronic LBP or other pain-characterized diseases. Future studies should focus on different LBP intensities and derive stratified HU that reflect the distribution of pain intensity in the population.

The overall aim of this thesis is to investigate treatment and prevention strategies for low back pain. The thesis is divided in two streams. Within the treatment strategies stream, Chapter Two provides an overview of the challenges to manage low back pain in Brazil, a middle-income country where low back pain is the condition with the highest disability burden. Chapter Three investigates the efficacy of antidepressants in people with spinal pain and osteoarthritis. Most antidepressants classes were ineffective for spinal pain. For those that were effective, the magnitude of the difference was small and not clinically important. Antidepressants seemed to be effective for people with sciatica, but the quality of the evidence ranged from low to very low. Chapter Four explores the care profile of people presenting to emergency departments with low back pain in Australia. This study found that, in people presenting to the ED with back pain, about half had a condition beyond the lumbar spine. In those with a lumbar spine condition, 69.6% received an opioid, 23.6% were imaged and 17.6% were admitted. Chapter Five presents the findings of a systematic review that examined the accuracy, comprehensiveness, and credibility of low back pain treatment recommendations from 79 websites. The included websites provided mostly inaccurate information, lack comprehensiveness and had low credibility standards. Within the prevention stream, the thesis focuses on exercise as a strategy for preventing recurrence of low back pain. Chapter Six explored the influence of participant and programme characteristics on people’s willingness to undertake exercise programmes to prevent recurrence of low back pain. Preferences for engaging in exercise programmes were influenced by the characteristics of the programmes themselves. However, there is mismatch between the preferred characteristics of exercise programmes and the characteristics of known effective programmes. In Chapter Eight the effectiveness of exercise and education compared to a minimal intervention in preventing recurrence of low back pain was investigated. Exercise and education were superior to minimal intervention in reducing new episodes of low back pain. A statistical analysis plan of the randomised trial was published a priori and is presented in Chapter Seven.

The evidence based management of low back pain (LBP) in primary health care has improved; however, there are still gaps related to risks, prognosis and treatment for this condition. This thesis contributes to the understanding of these gaps and provides insights into the influence of patient-clinician interaction in treatment outcomes. The case-control twin study presented in Chapter 2 was designed to identify new and important risks for LBP using twins’ perceptions of the contribution of various factors in the development of their own or their twins’ LBP. Patients’ reported sense of social isolation was investigated as a prognostic factor for LBP, and reported in Chapter 3. Effectiveness of self-management of LBP was investigated in a systematic review, reported in Chapter 4. The influence of the patient-clinician interaction on treatment outcomes was investigated in two systematic reviews, reported in Chapters 5 and 6, and in a cohort study, reported in Chapter 7. Overall, the studies presented in this thesis contributed new knowledge about risks, prognosis and treatment of LBP. Physical loading of the spine and lifestyle factors were perceived to be important risks for LBP, patients’ reported sense of social isolation may inform prognosis, and self-management of LBP appears to have limited benefit. This thesis also provided new knowledge about the influence of patient-clinician interaction on treatment outcomes. Firstly, modifiable communication factors during the patient-clinician interaction that predicted treatment outcomes over time were not identified. Secondly, clinicians simply facilitating further clarification of patients’ expressed emotions were insufficient to optimise treatment outcomes in LBP. Thirdly, communication training for clinicians has small benefits in terms of treatment outcomes and needs to be better understood and maximised to be useful in LBP.

Prior studies have reported differences in lower back biomechanics during activities of daily living between individuals with and without chronic low back pain (LBP). Nevertheless, the literature on lower back biomechanics of patients with non-chronic LBP is scant. Therefore, the objective of this study, as the first step towards future prospective studies, was to investigate the lower back biomechanics in patients with non-chronic LBP. Case-control studies were conducted wherein measures of lumbo-pelvic coordination during bending and return tasks as well as measures of mechanical demand on the lower back during lifting tasks in the sagittal plane were investigated between patients with non-chronic LBP and matched asymptomatic individuals. Patients were enrolled into the study at the non-chronic stage of their LBP. We found distinct difference in measures of lumbo-pelvic coordination as well as mechanical demands on the lower back between patients with non-chronic LBP and controls. Reduced lumbar range of flexion and slower task pace as well as the more in-phase and less variable lumbo-pelvic coordination observed in patients with non-chronic low back pain, may be the result of a neuromuscular adaptation to reduce the forces and deformation in the lower back tissues and avoid pain aggravation. Such a neuromuscular adaptation, however, resulted in a larger shearing demand on the lower back. Persistent abnormal lumbo-pelvic coordination might play a role in transition to chronic stage or recurrence of LBP. However, such inferences need to be further investigated using prospective studies as well as clinical trials involving a combination of physical and psychological treatments aimed at correction of lumbo-pelvic coordination.

This study used a qualitative method to focus on the perspectives, beliefs and expectations of low back pain sufferers. The research was undertaken within a hospital based pain clinic. In recent years low back pain research has proliferated, and the epidemiological evidence suggests that back pain is an increasing problem. Much attention has been paid to the impact of low back pain on the population, and to the increasing cost in economic and health terms. Biomedical and psychological evidence abounds to shape acute and chronic management of low back pain, but there is a dearth of information about the viewpoint of those suffering pain. This study attempted to bring the understanding of the back pain sufferer to the fore. Issues of quality of life, functional ability and the impact of back pain on their lifestyle were explored, along with the influence of contextual factors in relation to how back pain sufferers perceived themselves and how others perceived them. A narrative method was utilized to illuminate the journey with pain. Nine interviews were conducted, and the interpretation and presentation of the narratives generated was influenced by Ricoeur’s interpretative theory. Thematic analysis revealed that doctorability, agency, control, separation or acceptance of the pain and the concept of future life were key features within the narratives. The analysis highlighted that for the majority in this study pain arrived uninvited following a traumatic accident or incident, and back pain became a chronic condition. It was always unwanted and initially it was unexpected as the usual script for pain is one of a transient incapacity followed by recovery. It was precisely this deviation from the norm that resulted in difficulties for the people suffering the pain. Biographical differences did not appear to be identifiable in the themes discerned in the stories, nor in the overall structure.

Abstract The etiology of musculoskeletal disorders remains largely unclear, pain being the predominant complaint. The prevalence of neck pain (NP), shoulder pain (SP), and low back pain (LBP) increases drastically during adolescence. Potentially modifiable risk factors of NP, SP, and LBP should be identified at that age. First, this study evaluated the prevalence of NP, SP, LBP and peripheral pains (upper or lower extremities) and the prevalence of multiple pains. Second, the study determined the role of a set of potentially modifiable risk factors for adolescents’ NP, SP, and LBP (physical activity, inactivity, sedentary activities in cross-sectional study design and quantity and quality of sleep in follow-up study design). The study population belongs to the 1986 Northern Finland Birth Cohort (NFBC 1986), consisting of 9,479 children with an expected date of birth between July 1, 1985 and June 30, 1986 in the two northernmost provinces of Finland, Oulu and Lapland. NP, SP, and LBP were common at the ages 16 and 18, while medical consultations for these pains were less frequent. The prevalence of pain increased with age. Peripheral pains were rare. Surprisingly many adolescents reported multiple musculoskeletal pains. Girls were more likely to report pain than boys. Both low and high level of physical activity, some risk sport activities, high amount of sedentary activities, and insufficient quantity and quality of sleep increased the risk of NP, SP, and LBP in adolescence. It may be possible to reduce the occurrence of musculoskeletal pain by having a positive impact on potentially modifiable risk factors, such as physical activity, sedentary activities and sleep hygiene. Therefore, intervention studies focusing on these factors are needed in the future
Tiivistelmä Useimmiten tuki- ja liikuntaelinsairauksien tarkka syy jää epäselväksi ja kipu on niiden pääasiallinen ilmentymä. Niska-, hartia- ja alaselkäkipujen esiintyvyys väestössä nousee merkittävästi teini-iässä. Tämän vuoksi niska-, hartia- ja alaselkäkivun riskitekijöitä tulisikin tutkia nuoruudessa, jotta niihin päästäisiin vaikuttamaan ajoissa. Tässä väitöskirjassa selvitettiin niska-, hartia-, alaselkä- ja laaja-alaisten tuki- ja liikuntaelinkipujen esiintyvyyttä nuorilla. Päätavoite oli kuitenkin tutkia liikunnan, eri urheilulajien, liikkumattomuuden, istumisen ja unen laadun ja määrän yhteyttä niska-, hartia- ja alaselkäkipujen esiintyvyyteen. Tutkimusaineisto muodostui Pohjois-Suomen syntymäkohortin 1986 nuorista, joiden laskettu syntymäaika oli 1.7.1985–30.6.1986. Nuorille lähetettiin 16-vuotiaana postikysely, joka sisälsi tuki- ja liikuntaelinoirekyselyn, kysymyksiä liikunnan, istumisen ja unen määrästä ja laadusta, sekä muista elämäntavoista. Kahden vuoden kuluttua, 18-vuotiaana lähetettiin toinen kysely joka sisälsi mm. tuki- ja liikuntaelinoirekyselyn. Tulokset osoittavat että niska-, hartia- ja alaselkäkivut olivat yleisiä nuoruudessa, joskin hoitoa vaativat kivut ja raajojen kipuoireilu olivat harvinaisia. Laaja-alaiset tuki- ja liikuntaelinkivut olivat odotettua yleisempiä. Tytöt oireilivat enemmän kuin pojat ja oireilu lisääntyi iän myötä. Hyvin aktiivinen liikunnan harrastaminen (6h/vko tai enemmän ripeää liikuntaa) ja erityisesti tietyt riskilajit olivat yhteydessä suurempaan niska-, hartia- ja alaselkäkipujen esiintyvyyteen. Samoin suuri istumisen määrä, riittämätön uni ja huono unen laatu lisäsivät kipujen todennäköisyyttä. Nuorten tuki- ja liikuntaelinkipuja voitaisiin mahdollisesti vähentää vaikuttamalla muunneltavissa oleviin riskitekijöihin, kuten vähentämällä istumista, lisäämällä terveysliikuntaa, sekä parantamalla unitottumuksia. Tämän takia jatkossa tarvitaan näihin riskitekijöihin kohdistuvia interventiotutkimuksia

The thesis aimed to investigate the effectiveness of AT for LBP. A systematic review was conducted to determine the effectiveness of acupuncture. There is strong evidence that acupuncture can be a useful supplement to other forms of conventional therapy for non-specific LBP although the effectiveness of acupuncture compared with other forms of control intervention still requires further investigation.

Introduction: Lifetime prevalence of low back pain in the adult population has been estimated to be over 60% and the costs to society are huge. It has been calculated that the direct health care costs of the condition approach £2billion per annum in the UK alone, and further costs are associated with informal care and with lost productivity in the workplace. Prevalence of the condition increases with age from approximately 30% at age 25yrs and studies have shown that, in adults, the greatest predictor of low back pain is a previous history of similar symptoms. It is important, therefore, to examine the aetiology of low back pain in youth. In childhood low back pain is also reasonably common and some authors have published prevalence estimates approaching those in adults. A number of factors have been associated with the occurrence of low back pain in childhood and/or adolescence: physical factors, such as height and weight; mechanical factors, such as the carriage of heavy schoolbags; lifestyle factors, such as sports participation; psychosocial and psychological factors, such as behavioural conditions and a negative affect score; and familial factors, such as the presence of parental pain. However, the majority of published research in this field has been cross-sectional in nature and, therefore, cannot distinguish between cause and effect. To investigate the aetiology of low back pain it is clear that longitudinal studies that examine the onset of the condition are required. Aims: To identify the risk factors for the onset of low back pain in adolescents. Study Design: Population-based prospective cohort study. Methodology: Two cross-sectional surveys were carried out twelve months apart. At baseline, 1040 children aged 11-14yrs, from thirty-nine schools in the Northwest of England, were identified as being free of low back pain. In these children, average daily mechanical load was assessed using schoolbag weight, recorded over a five day period. Using a self-completion questionnaire, exposure to a number of other potential risk factors was assessed: lifestyle factors, psychosocial factors, and the occurrence of other common childhood (somatic) pain complaints. These children were then followed up twelve months subsequently to establish episodes of new onset low back pain. In addition, using a postal questionnaire, information was obtained from parents of the subjects regarding the occurrence of parental pain, and also, in girls, menstrual status. Results: 935 children (89.4%) participated at follow-up, of whom 168 (18.6%) reported low back pain - by definition, new onset low back pain. The occurrence of new onset low back pain increased with age and was more common in girls than boys but was unrelated to menstruation. The onset of low back pain was associated with neither average daily mechanical load, nor mechanical load relative to body weight. In general, lifestyle factors were not predictive of future pain, although sporting activity was significantly, but non-linearly, associated with an increased risk of pain. In contrast, adverse psychosocial factors were consistently and strongly associated with an increased risk of future pain; this was true for conduct problems in particular. Furthermore, the baseline occurrence of headache, abdominal pain and sore throats was associated with an increased risk of low back pain at follow-up. Children whose parents reported pain were no more likely to report low back pain (or indeed, any pain) than other children. Conclusions: This study has provided no evidence that mechanical factors are associated with an increased risk of future low back pain. Adverse psychosocial behaviour, and conduct problems in particular, are associated with an increased risk of new onset low back pain. In addition, the prior occurrence of other common pain conditions was strongly associated with an increased risk of future pain. Thus, this study concludes that low back pain in childhood may be a manifestation of somatisation.

This thesis presents a set of studies which investigated chronic low back pain. The specific aim of this thesis was to develop reliable methods for the assessment and rehabilitation of chronic low back pain. The two assessment methods tested were a broad based clinical evaluation and an isokinetic assessment of trunk muscle strength. The first part of the thesis describes the reliability and validity studies of the clinical methods for measuring trunk mobility, trunk muscle strength, spinal shape and palpation. A total of 27 physical tests were studied using 70 patients and 10 normal subjects. Twenty-three of these tests were found to be reliable and were incorporated into the isokinetic assessment study. The second part of the study reports the standardisation and reliability studies for the isokinetic assessment of trunk muscle strength in 70 normal subjects and 120 patients with chronic low back pain. The results showed that the main isokinetic measures were reliable for both normal subjects and patients. There was a significant learning effect from test 1 to test 2 in both normal subjects and patients. The magnitude of this learning effect was greater in patients than normal subjects. The normal subjects were followed up by a postal questionnaire in a two year prospective study to predict future back pain using the isokinetic measures. None of the measures used showed any significant differences between those subjects who developed back pain and those who did not. The third part of the thesis describes studies to develop a rehabilitation programme for patients with chronic low back pain using the isokinetic machines, both as a means of monitoring progress and as an exercise regime. The first study of 26 patients indicated that the programme was safe and effective, but also revealed a major problem with adherence to a six week exercise programme. The second study investigated the problem of adherence and examined the time course of response to isokinetic exercise by repeating the tests at three weeks and six weeks.

DEPRESSION AND RISK FACTORS FOR LOW BACK PAIN Abstract Although low back pain has been widely studied, our understanding of risk factors, as well as the impact of comorbidities on low back pain, remains limited. The broad aim of this thesis was to investigate the association between low back pain and common risk factors, namely symptoms of depression, sleep problems, and physical activity, by conducting a series of studies. Four studies (Chapters Two to Five) were carried out to explore the relationship between low back pain and symptoms of depression. Taken together, the results of these studies suggest that a causal relationship between low back pain and symptoms of depression is weak, at best. The influence of symptoms of depression to the risk of low back pain is more complex than previously thought, and likely to be dependent on people’s genetic susceptibility. Additionally, the findings suggest that symptoms of depression have a negative impact on the prognosis of low back pain. Chapter Six investigated the association between low back pain and sleep problems and the results showed that, to some extent, there is an overlap in the set of genes affecting both sleep quality and low back pain. Lastly, this thesis described the protocol (Chapter Seven) and preliminary results (Chapter Eight) of the feasibility investigation for the AUTBACK study – a study that investigates the effects of physical activity on low back pain. The employment of a twin design to investigate the effects of physical activity for low back pain has proven to be feasible in terms of follow-up rate and completeness of data. This approach is promising and opens a new frontier for the consideration of the genetic effects on the relationship between physical activity and low back pain. The findings of the studies reported in this thesis have advanced our understanding of the relationship between low back pain and commonly reported risk factors such as depression, sleep, and physical activity.

Low back pain is a debilitating condition that afflicts millions of people each year. It is characterized by complex biochemical, morphological, and biomechanical changes. However, most believe low back pain arises due to abnormal mechanical loading, inflammation, and disc degeneration. Several studies have investigated radial back pain, but to date, there is only one in vivo animal model for low back pain. Despite advances in science, the causes of low back pain remain unclear and treatments fail to relieve the pain. To better understand the causative factors of low back pain, a reliable animal model is needed. This study was designed to advance the knowledge of the previous in vivo animal model for low back pain by investigating the effects of shear loading on disc degeneration (for a longer duration of time) and discogenic low back pain (in terms of immunohistochemistry) in hopes developing better treatment strategies for low back pain sufferers and to help elucidate the etiology of low back pain. Adult male Sprague Dawley rats (n=31) were shear loaded for 4- and 8- weeks. Pain behavioral testing was done prior to and after surgery. After sacrifice, immunohistochemistry was used to detect the presence of pain in the intervertebral discs and the spinal cord. Results of this study indicate that the application of an abnormal shear load gives rise to disc degeneration. Histology revealed that all loaded levels as well as the adjacent levels degenerated due to the shear load. Pain behavior testing revealed that the rats did experience pain, however, when combined with the immunohistochemical results, we were able to exclude the pain as pain stemming from the degenerated discs. Surprisingly, we observed that shear loading caused scoliosis of the thoracolumbar spine.

Low back pain is a common but severe health problem. Chronic low back pain accounts for the bulk of the burden of low back pain. Exercise interventions are effective in the management of chronic low back pain. Current clinical thinking in physical therapy treats low back pain as a heterogeneous entity seeking to match specific interventions to subpopulations. None of these subgroups assess the role of gluteus medius dysfunction in chronic low back pain. These projects seek to describe the prevalence of gluteus medius weakness in people with chronic low back pain and test the effectiveness of a gluteus medius strengthening exercise intervention in people with chronic low back pain. Gluteus medius strength was assessed in 150 people seeking care for chronic low back pain and 75 healthy people without low back pain. Gluteus medius was found to be weaker on affected sides compared to unaffected sides within people with chronic low back pain and weaker than people without low back pain. Gluteus medius weakness was a strong predictor of the presence of low back pain. A gluteus medius strengthening program was compared with lumbar stabilization exercises in 56 people with chronic low back pain. Although there was a clinically significant improvement in pain in people who performed the gluteus medius strengthening exercise program, this was not significantly different from the stabilization exercise intervention. Adherence to exercise was significantly correlated with reduction in pain and perceived improvement of low back pain. Although gluteus medius weakness is common in people with low back pain and treating this weakness with a targeted exercise intervention is effective, it is not better than a standard stabilization exercise intervention. Doing exercise is likely more important than what exercise is done.

This thesis investigates position awareness of the low back, measured using an electrogoniometer, in participants with and without recurrent non-specific low back pain (NSLBP). The ability to appreciate body position and movement makes an essential contribution to control of posture and functional movement. Pain may impair this awareness and initiate or exacerbate joint damage. Impairment of position awareness in the low back has been reported in patients with chronic low back pain. In addition, work-related activities may impair positional awareness, particularly in people experiencing LBP. The accuracy, stability and through range test-retest reliability of the electrogoniometer was assessed. It was found to be a reliable measure of degrees during movement in the sagittal plane between 0 to +/- 60 degrees, when compared to measurements using a calibrated, highly accurate, bevel protractor (mean error differences below 0.5 degrees for all tests). Low back position awareness was measured before and after a shift of work, in sitting and standing, in 61 people with recurrent NSLBP and 40 without a history of LBP. In addition, secondary analysis investigated the effect of occupation (manual workers, sedentary workers, drivers) on position sense. Low back position awareness was also measured in 50 people with recurrent NSLBP and 50 without a history of LBP during mid-range of sagittal plane movement of the low back in sitting; and when trying to return to a "good" sitting posture. There were no differences between participants with and without recurrent NSLBP in repositioning accuracy of the low back during any of the studies. When investigating the effect of occupation however, only sedentary workers achieved the power required for analysis. People with LBP positioned their "good" sitting posture significantly closer to end-range of low back extension, than people without LBP (12.47 SD8.46, v’s 16.51 SD9.41 degrees respectively; P=0.026). Recurrent NSLBP and sedentary work-related activities did not affect accuracy of position awareness in the low back. In people with recurrent NSLBP however, the position of their "good" sitting posture closer to end-range low back extension could lead to greater compressive loading of pain-sensitive spinal tissue, as well as increases in facet joint forces and shear forces on discs. These mechanisms may be aetiologic in the recurrence and maintenance of LBP. This finding may have implications for clinical practice, with consideration perhaps given to assessing the position of "good" sitting posture and its relationship to end-range in patients with LBP. Future research should investigate this further in larger populations of people with and without LBP, including specific sub-groups of LBP.

The aim of this thesis was to explore whether known psychosocial and other determinants of chronic low back pain (CLBP) associated disability were relevant in the context of a Saudi Arabian culture. The thesis comprises four studies. A systematic review and meta-analyses (Chapter 3) determined the relationship between disability and selected psychosocial and cultural factors among non-English speaking populations with LBP. Pooled correlation coefficients revealed medium effects for the association of lower disability with greater self-efficacy, reduced pain-related fear, less catastrophic thinking, and negative back-pain beliefs. The influence of cultural factors on disability was limited to geographical region and spoken language. Chapter 4 explored the development and selected psychometric properties, of a new pain behaviour scale (PaBS) measuring the presence and severity of observable pain behaviours in a discrete Saudi CLBP population. The PaBS showed excellent inter-rater and intra-rater reliability and acceptable construct validity. Building on the outcomes of these two studies, the multidimensional clinical profile and determinants of CLBP disability were cross-sectionally explored in a larger Saudi cohort (Chapter 5). Multivariate regression revealed higher pain intensity, fear avoidance beliefs, and psychological distress, and increased age, were associated with greater disability, explaining 52.9% of variability. Finally, the predictors of ongoing CLBP disability at 12-month follow-up were investigated (Chapter 6). Higher pain intensity, fear avoidance of work, and increased age explained 53.0% of the variability in higher disability, while having no additional somatic symptoms predicted lower disability. This thesis has generated new knowledge regarding the multidimensional nature of CLBP and identified key prognostic factors that clinicians can consider in practice to identify those at risk of ongoing disability in Saudi Arabia.

Low back pain (LBP) is a well-recognized worldwide health problem due to its high prevalence and substantial economic impact. Despite abundant research on risk factors for LBP, the causes in the majority of cases remain unknown. One of the plausible modifiable risk factors, obesity, has been commonly investigated in the field. However, despite a considerable number of published studies exploring the relationship between obesity and LBP, the nature of the relationship remains unclear. To overcome this gap in the literature, this thesis reports a series of four studies - one systematic review and three observational studies - designed to evaluate whether obesity-related measures are risk factors for LBP in twins. Theoretically, the twin design permits a more robust examination of obesity as a risk for LBP as it allows the control for genetic and early environmental influences on this relationship. The results of the twin studies presented in this thesis provide novel information that allows a better understanding of the complex relationships between obesity and chronic LBP. Although obesity and chronic LBP often coexist, a direct link between the two is questionable. Firstly, in the cross-sectional analyses, the magnitude of associations was mostly weak. When high levels of control for important confounding factors such as genetics was applied, the associations did not remain significant. In twin pairs discordant for LBP status, no between-twin difference was observed in obesity-related measures. Lastly, obesity-related measures do not seem to increase the risk of chronic LBP as no temporal effect was observed. Consequently, these results indicated that obesity coexist with the presence of LBP possibly due to common genetic or environmental influences on their pathogenesis, but a causal link between them is unlikely. In light of the new evidence, novel study directions have been proposed in regards to innovative preventative and management approaches for LBP.

The broad aim of this thesis was to contribute to a better understanding of the mechanisms and management of non-specific low back pain (LBP) by investigating treatment options, mechanisms and outcomes. Chapter Two provides an overview of risk factors for LBP in an umbrella review of the evidence revealing that individual, biomechanical and psychosocial factors increase risk for a future episode of LBP and sciatica. The study presented in Chapter Three aimed to investigate the extent to which patients can accurately nominate what has triggered their new episode of sudden onset, acute LBP. This study provides evidence that patients can clearly identify an activity that triggered their sudden-onset acute LBP. Chapter Four is a cohort study investigating the course of LBP in older men, if comorbidities/ lifestyle factors can predict the course of LBP in older men and if comorbidities/ lifestyle can increase the risk of developing LBP in older men. Two years after entering the study, older men continued to experience pain. Also, the higher number of comorbidities increased the odds of developing LBP and lifestyle factors influenced its course. Chapter Five investigated the effect of Back School on pain and disability for adults with chronic non-specific LBP in a Cochrane systematic review. Regardless of the comparison used (as well as the outcomes investigated), the results of the meta-analysis shows no difference or a trivial effect in favour of the Back School intervention. Chapter Six appraised the recommendations and methodological quality of international clinical guidelines for the management of vertebral compression fractures. The comparison of clinical guidelines for the management of vertebral compression fractures shows that diagnostic and therapeutic recommendations are generally inconsistent. The evidence available to guideline developers is limited in quantity and quality. Chapter Seven described the evolution of guideline-endorsed red flags for fracture in patients presenting with LBP and described the consistency between guidelines in the endorsement of red flags for fracture. The results shows that the number of red flags endorsed in guidelines to screen for fracture has risen over time; most guidelines do not endorse the same set of red flags and most recommendations are not supported by research or accompanied by diagnostic accuracy data. The studies in this thesis have provided an important contribution to the understanding of contemporary management of LBP. The main implications are: i) individual, biomechanical and psychosocial factors increase risk for a future episode of LBP and sciatica.; ii) patients can accurately nominate an activity that triggered their sudden-onset acute LBP: iii) LBP is typically persistent in older men and a higher number of comorbidities increased the odds of developing LBP; and lifestyle factors such as higher BMI and higher consumption of alcohol influenced its course iv) Back Schools showed no difference or a trivial effect for chronic LBP regardless of the comparison used v) Recommendations in clinical practice guidelines on vertebral compression fractures interventions should be reviewed vi) The number of red flags endorsed in guidelines to screen for fracture has risen over the years; most guidelines do not endorse the same set of red flags.

The prevalence of low back pain has assumed an upsurge trend in the last five decades despite the many interventional strategies. One interventional strategy that has been unsuccessful has been patient education. Lack of positive results from many of the existing patient education programmes is probably due to the type of health information that has been presented and the method that has been used. Many of the health education programmes have been planned according to what the medical professionals assumed the individuals needed to know, assumptions that could have ignored some crucial aspects. This study explored the perceived health education needs of individuals with low back pain at the Nairobi Hospital Rehabilitation Unit in Kenya, the method used to educate the individuals, the appropriateness of the method according to the individuals in addition to identifying the source of the health education that the individuals had.

Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.
Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Epidemiology, School of Public Health." Discipline: Epidemiology; Department/School: Public Health.

Context: Hundreds of thousands of Quebec residents suffer from chronic pain, for which treatment is far from optimal. Despite low back pain being the second most common reason to visit a primary care physician, management remains challenging. Additionally, chronic low back pain (CLBP) has been found to be the most common reason for patients to be referred to tertiary pain centers. Recently, there has been an increasing acceptance that bio-psycho-social factors play a crucial role the clinical course of CLBP. Objectives: The purpose of this study was to identify subgroups of CLBP patients treated in tertiary care, as defined by their changes in pain and disability over time, and to explore possible characteristics associated with these changes. Specific objectives were: 1) to establish whether there are distinct subgroups of patients with CLBP with different characteristics associated with change in pain and disability at 6, 12, and 24 months following an initial visit in a tertiary pain clinic; and 2) to identify potential social, psychological, biological, and environmental factors that may predict their responses in pain intensity and disability in accordance with the Revised Wilson and Cleary Model for Health-Related Quality of Life. Design: Observational prospective design to follow a cohort of patients who were enrolled in the web-based Quebec Pain Registry. Setting: The Quebec Pain Registry, a research database comprised of close to 5000 chronic pain patients. Eligible participants included all patients who 1) have been diagnosed with lumber without radicular pain, LBP (diagnostic code 3.1), lumbar & radicular pain, LRP (diagnostic code 3.2), or diffuse lumbar pain, DLP (diagnostic code 3.4), 2) who provided written consent for their data to be used for research purposes, and 3) have completed their initial visit to the pain clinic by May 31, 2011. Intervention: The data required for this project had previously been collected and entered in the Quebec Pain Registry. Basic descriptive results were produced using SAS® software 9.2. This analysis described the characteristics of the 917 patients included in the study at baseline. Additional data were explored to examine patterns of changes over two years for certain characteristics. A generalized estimating equations model (GEE) was used to analyze data at 6, 12, and 24 months after the initial visit. Results: 299 (32.6%) patients were diagnosed LBP, 522 (56.9%) with LRP, and 96 (10.4%) with DLP. In general, all patients were relatively comparable in terms of their characteristics with the exception of DLP, where proportions were noticeably different. Patients diagnosed with DLP had a higher pain duration median (6.0 years) and the most frequently current employment status was permanent disability (both in regards to proportions). The most common ethnicity was Caucasian among all diagnoses. Income was similarly distributed among all groups and secondary school was the highest level of education completed for all. The top three medical conditions reported other than CLBP were rheumatoid arthritis/osteoarthritis, hypertension, and depressive disorders. DLP patients reported "accident at work" as the most common circumstance surrounding their onset of pain. DLP also had noticeably different mean scores for average pain, worst pain, depression, catastrophizing, disability, mental and physical summary scores on the health-related quality of life questionnaire at baseline, 6, 12, and 24 months (in regards to proportions). Patients with higher worst pain scores, longer pain duration, and lower physical summary scores at the initial visit were significantly less likely to show improvements in pain intensity and disability at six and 12 months. Conclusions: Although modifying the analysis prohibited conclusions for a two-year follow to be made, characteristics, such as worst pain, pain duration, and lower physical summary scores at both six and 12 months were discovered.
Contexte: Des centaines de milliers de résidents du Québec souffrent de douleurs chroniques. En dépit de la douleur au bas du dos étant la deuxième cause la plus fréquente de consulter un médecin de soins primaires. . Récemment, il y a eu une acceptation croissante que les facteurs bio- psychosociale (biologiques, psychologiques et sociaux ) jouent un rôle crucial de l'évolution clinique de la lombalgie chronique , mais peu de recherches concernant la lombalgie chronique ont étés achevé plus d'un an . Objectif: Les objectifs spécifiques sont : 1) d'établir s'il existe des groupes distincts de patients atteints de lombalgie chronique avec des caractéristiques de réponse à 6, 12 et 24 mois après la visite initiale, et 2) pour identifier le potentiel social, psychologique, biologique et environnemental caractéristiques, conformément à la modèle révisée Wilson et Cleary pour la qualité liée à la santé de la vie. Conception: analyse prospective d'une cohorte historique. Cadre: Le Registre québécois de la douleur, une base de données de recherche unique composée de près de 5000 patients souffrant de douleurs chroniques de centres de la douleur tertiaires. Participants: adultes diagnostiqués avec la douleur chronique au bas du dos qui sont inscrits dans le registre de la douleur Québec. Les participants admissibles inclus tous les patients qui ont été diagnostiqués avec le bois sans douleur radiculaire , LBP (code de diagnostic 3.1), lombaire et douleur radiculaire , LRP (code de diagnostic 3.2) , ou une douleur lombaire diffuse , DLP (code de diagnostic 3.4) et ont terminé leur formation initiale visite à la clinique de la douleur avant le 31 mai 2011. Intervention: Les données nécessaires à ce projet avaient déjà été recueillies et consignées sur le registre de la douleur Québec. Résultats descriptives de base ont été produites en utilisant SAS ® 9.2 logiciel. L'analyse descriptive a décrit les 917 patients inclus dans l'échantillon de l'étude au départ, générant des scores moyens. Des données supplémentaires ont été explorées pour observer des modèles sur deux ans pour certaines caractéristiques. Un modèle des équations d'estimation généralisées (GEE) a été utilisé pour analyser des données corrélées à six, 12 et 24 mois. Résultats: 299 (32.6%) patients ont été diagnostiqués LBP, 522 (56.9%) avec LRP, et 96 (10.4%) avec DLP. En général, tous les diagnostics étaient comparables à l'exception de DLP. Les patients diagnostiqués avec DLP avaient une durée médiane de la douleur plus élevé (6,0) et l'invalidité permanente le plus fréquemment rapporté pour le statut actuel de l'emploi. L' ethnie la plus fréquente était de race blanche parmi tous les diagnostics . Le revenu a été distribué similaire dans tous les groupes, et à l'école secondaire était le plus haut niveau de scolarité atteint pour tous. Les trois conditions médicales rapportées étaient la polyarthrite rhumatoïde / arthrose, l'hypertension et les troubles dépressifs. DLP patients ont signalé « accident du travail » comme circonstance la plus courante qui entoure leur apparition de la douleur. DLP a également indiqué sensiblement différents scores moyens pour la douleur moyenne, pire douleur, la dépression, catastrophisme, le handicap, le score résumé mental, et le score résumé physique au départ, 6, 12 et 24 mois. Les patients ayant les plus mauvais scores de la douleur, la durée de la douleur plus élevé, et des scores plus bas sommaires physiques étaient significativement moins susceptibles de montrer des améliorations dans la douleur et le handicap à six et 12 mois. Conclusions: Bien que la modification des conclusions interdites d'analyse pour un suivi de deux ans à faire, des caractéristiques importantes telles que la pire douleur, la durée de la douleur, et les scores sommaires physiques inférieurs aux deux six et 12 mois ont été découverts.

Introduction Low back pain (LBP) is a leading cause of disability worldwide. Dancers, who are often required to perform complex and repetitive movements of the spine, are thought to be vulnerable to LBP. However, there is limited available evidence concerning the prevalence, experience, impact, or factors associated with LBP in this population. Therefore, the overarching aim of this thesis was to investigate the prevalence and factors associated with LBP in dance. Methods This thesis consists of five discrete but interrelated studies. Study one systematically synthesises the available evidence for the prevalence of, and risk factors for, LBP and injury in dance populations. Studies two and three investigates the prevalence and risk factors for LBP in multiple pre-professional and professional contemporary dance and classical ballet cohorts. Lifetime prevalence of LBP is determined using a cross-sectional study design. Monthly prevalence, duration, and impact of LBP episodes are investigated prospectively. Multivariable logistic regression is used to examine for individual and demographic factors associated with LBP. Studies four and five investigate the interaction between dance, LBP, and spine kinematics. To do so, they employ three-dimensional motion analysis and a multi-segment spine marker set. Posture as well as clinical and functional movement tasks common in LBP assessment are examined in dancers and non-dancers with and without LBP. Results The systematic review supported that dancers appear vulnerable to the experience of LBP. However, due to the heterogeneous nature of available research, and an absence of multivariable statistical analysis, clarity regarding the prevalence and risk factors for LBP remains limited. The need for multi-site epidemiological studies that employ definitions sensitive to the nature of LBP and that use appropriate statistical methods to investigate risk factors for LBP within dance populations was identified. The cross-sectional study revealed 74% of pre-professional and professional dancers had a history of LBP. Prospectively, 52% of dancers experienced activity limiting LBP and 24% suffered from LBP that was chronic in duration. Prior experience of LBP preceded the experience of future episodes of LBP (adjusted odds ratio: 3.98; 95% confidence interval: 1.44, 11.00; p < 0.01). There was no association between personal or demographic factors and LBP. With respect to spine kinematics, female dancers presented with a flatter upper lumbar spine posture (p< 0.01, ηp2 = 0.15) in the sagittal plane and increased upper lumbar (p=0.04, ηp2=0.08) and lower thoracic (p=0.02, ηp2=0.09) frontal plane range of motion than non-dancers. However, there was no interaction between these measures and LBP. During walking gait, female dancers with recent LBP displayed a moderate reduction in transverse plane ROM for the lower lumbar spine (effect size (ES)=-0.65, 95% CI: -1.24, -0.06, p=0.03), and a moderate increase in lower thoracic transverse plane ROM (ES=0.62, 95% CI: 0.04, 1.21, p=0.04) compared to asymptomatic dancers. Conclusion Dancers are vulnerable to the experience of LBP. However, there is considerable variation in the time-course and impact of LBP episodes. History of LBP predicts future episodes, which supports that LBP is rarely limited to a single episode. Beyond this, the factors associated with LBP are complex and not easily discerned. With respect to movement, an altered movement strategy during walking gait suggests that female dancers with LBP may compensate for reduced mobility in painful regions by increasing mobility in other regions. However, these movement strategies are subtle, and the overall number of biomechanical differences was limited. Whether this indicates dance training protects against biomechanical changes normally associated with LBP, or suggests dancers are intrinsically different to non-dancers requires further consideration.

Low back pain (LBP) is a common condition presenting in primary care. It represents a significant health and economic burden. The findings from this thesis have shed new light onto the efficacy of commonly used interventions such as over-the-counter medicines, prescription opioid analgesics, muscle relaxants and advice for the management of LBP. Muscle relaxants, NSAIDs, rubefacients and local heat application are effective in the management of acute LBP, whilst opioid analgesics have shown some benefit on pain (but not disability) in chronic LBP. The findings also show that pain relief at opioid analgesic doses beyond the maximum recommended, is not likely to be clinically significant. This thesis has also identified a need among pharmacists for decision support tools to assist them in the management and triage of people with LBP. Given the findings from the simulated patient study, the tools must serve to promote evidence-based non-pharmacological management of LBP since this was an area that was broadly lacking. Encouraging effective counselling around appropriate self-care advice will also help strengthen the management of LBP in primary care. In conclusion, greater focus on LBP education at the undergraduate or postgraduate pharmacy training level may serve to bridge the knowledge and practice gaps identified.

Chronic low back pain (CLBP) exerts a significant burden on the individual and society. To date, despite a large amount of research conducted in this field no treatment offers effective and sustainable improvements in outcomes. A patient-centred care approach, that takes into account the person with CLBP, their values and skills set, and encourages the person to take the lead in their own management, is said to facilitate self-management. Goal setting is an intervention most commonly used to facilitate behaviour change and is a common component of self-management programs. Several theories underpin the mechanism of goal setting that suggest that a person’s motivation will be enhanced if the goals reflect what is of value to them. Research shows that goals set by therapists often do not reflect the preferred goals of the patient and the intervention is driven by what the therapist believes to be important rather than what is important to the patient. In this instance the treatment no longer remains patient-centred. Research investigating goal setting in CLBP remains sparse and the extent of patient involvement in the process is unknown. The effects of goal setting where the patient is placed at the centre of the intervention has not been investigated. To address these issues, this thesis aimed to: a) determine the influence of physiotherapists’ beliefs and attitudes about chronic low back pain on clinical practice; b) investigate the current goal setting practices of physiotherapists for chronic low back pain and the influence of attitudes and beliefs of physiotherapists on goal setting practice; c) identify goals set by patients with chronic low back pain and compare these goals to the most commonly used outcome measures in chronic low back pain; d) investigate the feasibility and preliminary effectiveness of a patient led goal setting intervention for chronic low back pain; and e) investigate the effectiveness of a patient led goal setting intervention for chronic low back pain in a randomised controlled trial. To investigate the beliefs and attitudes of physiotherapists and their influence on clinical practice in CLBP a systematic review including both quantitative and qualitative studies was conducted. Quantitative studies (N=5) reviewed showed a higher biomedical treatment orientation score was associated with advice to delay return to work and return to activity, and a belief that return to work or activity is a threat to the patient. Physiotherapists’ fear avoidance scores were positively correlated with increased certification of sick leave and advice to avoid return to work and return to normal activity. The qualitative studies (N=5) reviewed revealed two main themes attributed to beliefs and attitudes of physiotherapists that had a relationship to the clinical practice of physiotherapists in CLBP – (1) treatment orientation and (2) patient factors such as beliefs and treatment expectations. In addition, adherence to clinical guidelines by physiotherapists was low. To investigate current goal setting practices a cross-sectional survey of registered physiotherapists (N=239) in New South Wales, Australia, was conducted. The aims of the study were to explore current goal setting practice in CLBP amongst physiotherapists, perceived barriers to goal setting in CLBP and the relationship between attitudes and beliefs and goal setting practice. Results revealed that the majority of respondents used goal setting with all patients, with the main aim of facilitating self-management. The goal domain in which most goals were set was activity tolerance (N=193, 93.7%) and the greatest number of respondents’ reported goals were set with 50% therapist / 50% patient involvement (N=93, 45.1%). Setting goals and involving the patient in goal setting was mostly seen as a high priority amongst respondents. However, under 10% of survey respondents involved their patients fully in the goal setting process, with the majority of therapists collaboratively setting goals using varying levels of patient involvement. The most common perceived barriers to goal setting were those relating to time constraints; prioritising goal setting activity over other tasks; staffing levels; lack of confidence in goal setting skills; and inadequate goal setting training. Statistical analysis showed a significant linear trend between measures of patient involvement in goal setting and treatment orientation, where a higher biomedical treatment approach score was associated with a lower measure of patient involvement (P<0.05; R2 =0.259), and there was a significant positive association between behavioural treatment approach score and measure of patient involvement overall (P<0.05; R2=0.118). These survey results revealed that physiotherapists set goals with varying degrees of patient involvement despite the belief that involving the patient is a high priority. Drawing on theory and the findings of the first two studies, it was postulated that a more strongly oriented patient-centred approach to goal setting may enhance the alignment between physiotherapists’ treatment goals and what is important to the patient. In addition, in light of the lack of published literature regarding the effectiveness of such an approach in the management of CLBP, it was further postulated that an intervention focussing on patient preferences for goal setting would result in significant improvements in indices of CLBP. To these ends, a patient led goal setting intervention was developed and tested for feasibility. The study investigated patient goals in CLBP, their relationship to clinical outcome measures, and their correlation with the most common measures used in physiotherapists in clinical and research settings. A single group longitudinal cohort pilot study was conducted. Twenty participants were involved in a two month patient-led goal setting intervention, facilitated by a physiotherapist. A total of 63 individual goals and 27 unique goals were identified. The majority of participants had more than one goal relating to two or three domains. Comparison of participant goals to the most common measures used by physiotherapists, such as pain, range of motion and strength found that none of the goals could be aligned. Comparison of participant goals and domains with the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) consortium six core outcome domains found 76% of the goals were aligned with physical functioning and 16% with emotional functioning. With respect to outcome measures, disability, pain intensity, quality of life, self-efficacy, fear avoidance, anxiety and stress all improved significantly over time (repeated measures ANOVA, P<0.05). Specifically, disability, pain intensity, quality of life, self-efficacy and fear avoidance measures improved significantly between baseline and two months (paired sample t-tests, P<0.05). Improvements in these measures as well as anxiety remained significantly better at follow up (four months) than baseline and were similar to the two month scores (paired sample t-tests P>0.05). These findings confirm that a patient led goal-setting intervention is a potentially effective intervention for the management of CLBP, showing significant improvements in both psychosocial and physical domains. To strengthen and further evaluate the evidence for a patient led goal setting approach a larger, more robust study was conducted. This final study comprised an assessor-blinded prospective randomized controlled trial (RCT) with two arms - (i) patient led goal setting (N=37), and (ii) usual care (N=38). Primary measures of disability and pain intensity, and secondary measures of quality of life, fear avoidance and self-efficacy were taken at baseline (pre-treatment), two months (post treatment), four months and 12 months. Analysis with intention to treat was undertaken. Generalised linear model analysis showed mean differences in change scores were significantly higher in the intervention group for all measures (P<0.001). Furthermore changes in mean scores for the intervention group were clinically worthwhile. Healthcare utilisation data were collected at baseline, four months and 12 months. No significant differences in healthcare utilisation were found between groups. Conclusion The research reported in this thesis provides evidence of the importance and clinical value of taking into account the preferences of the patient in the management of CLBP. Findings showed that beliefs and attitudes of physiotherapists regarding treatment orientation towards CLBP influence clinical practice, which in turn affect the level of patient involvement they undertake. Whilst goal setting in CLBP is perceived as a high priority amongst physiotherapists, it is practiced with varying degrees of patient involvement. Compounding this, patient goals differ from therapist goals and are not aligned with measures used in clinical and research settings. Together these findings suggest that delivering truly patient-centred care is a challenge. The results of the patient led pilot and RCT studies showed that a more strongly aligned patient centred approach which enabled the patient to lead the goal setting and drive the direction of treatment was effective in the treatment of CLBP. Significant improvements were achieved in disability, pain intensity, quality of life, fear avoidance and self-efficacy. Importantly, these improvements were maintained in the long term. The findings reported in this thesis challenge current thinking and practices regarding treatment approaches to CLBP. The findings suggest new pathways to providing an effective model of care for a significant proportion of the community living with a long-term and debilitating condition. Central to achieving this is the need for a focus on education, at both the higher education level as well as professional level, so that physiotherapists have the skills and confidence to work with their patients. It is intended that this thesis will contribute to a move towards a more inclusive and patient led approach to the management of chronic low back pain.

Low back pain is common and causes more burden in terms of years lived with disability than any other health condition globally. In most cases, the patho-anatomical cause of low back pain cannot be determined. Less commonly, specific spinal pathologies can be identified as the cause of low back pain, including conditions involving neurologic compromise, such as sciatica and lumbar spinal stenosis. Despite extensive research over the past decades, questions remain in terms of the underlying mechanisms, risk factors, and current treatment options for these conditions. The broad aim of this thesis, therefore, is to contribute to a better understanding of factors associated with low back pain onset and the safety and efficacy of contemporary management strategies. Risk factors associated with the onset of a new episode of low back pain can be divided into those involving long-term exposure (e.g., smoking) and those involving transient or brief exposure to the risk factor (e.g., a fall). A recent case-crossover study identified that commonly endorsed physical and psychosocial triggers (e.g., awkward postures, distracted during an activity) increase substantially the risk of sudden onset low back pain, with odds ratios ranging from 2.7 to 25.0. This study focussed on triggers for an acute episode of low back pain and did not consider the triggers that increased the risk of an episode of longer duration. This is an important issue as most of the costs of low back pain are associated with persistent cases. The study presented in Chapter Two includes the 12-month follow-up of this case-crossover study and examined the association between the previously identified triggers and the risk of a low back pain episode that persisted for greater than six weeks. This study was based on data from 782 patients presenting to primary care clinics for a new episode of low back pain, who were successfully followed-up. Conditional logistic regression models suggested that previously identified psychosocial and physical triggers, such as being fatigued or tired during an activity or manual tasks involving awkward postures, increased the risk of persistent episodes of low back pain, with odds ratios (OR) ranging from 2.9 (95% confidence interval [CI]: 1.3–6.4) to 11.7 (95% CI: 5.4–25.3). The results were similar to those for acute episodes of low back pain, suggesting that controlling exposures to these triggers may prevent not only the cases of low back that resolve within six weeks, but also the cases that persist, which are believed to cause the greatest burden of this condition. While a great proportion of patients with low back pain experience recovery within six weeks, recurrence of low back pain is common. However, estimates of recurrence within one year range from 26% to 84%. Part of this variability can be attributed to different definitions of episodes of low back pain used across studies. Moreover, only a few studies have used appropriate methodology to investigate predictors of recurrence. The study presented in Chapter Three determined the 1-year incidence of recurrence in participants who had recently recovered from an acute episode of low back pain, and identified predictors of future recurrences. This was an inception cohort study with 12 months follow-up. Recurrence was defined based on a 12-month recall of a new episode of pain or a new episode of care seeking with data from 469 participants. The 1-year incidence of recurrence of low back pain was 33%, and the recurrence rate for a new episode of care seeking for low back pain was 18%. Multivariable regression analysis revealed that having more than two previous episodes of low back pain increased the odds of a future recurrence by 3.2 (95% CI: 2.1–4.8). This factor was also associated with recurrent episodes of care seeking (OR: 2.9, 95% CI: 1.7–4.8). No other factors were associated with recurrence. This study contributes to the lack of research on recurrence of low back pain. Patients with low back pain seeking primary health care are often recommended paracetamol as the first line analgesic medication. This medicine is also widely used to treat osteoarthritis. However, a randomised trial published in 2014 concluded that paracetamol was ineffective for acute low back pain, and there was also conflicting evidence for its use in osteoarthritis. The systematic review with meta-analysis of randomised placebo-controlled trials presented in Chapter Four investigated the safety and efficacy of paracetamol in patients with low back pain, as well as neck pain, or osteoarthritis. Searching eight databases revealed 13 trials that met the inclusion criteria. Pain and disability scores were converted to a 0 to 100 scale, and a 9-point threshold was used to define smallest worthwhile effect. Pooling showed no effects of paracetamol on pain (mean difference [MD]: –0.5, 95% CI: –2.9 to 1.9) or disability (MD: 0.4, 95% CI: –0.9 to 1.7) for acute low back pain. No trials investigated the effects of paracetamol for patients with neck pain. Paracetamol had small and not clinically important effects for osteoarthritis in pain relief (MD: –3.7, 95% CI: –5.5 to –1.9) or disability reduction (MD: –2.9, 95% CI: –4.9 to –0.9). Patients taking paracetamol were 3.8 times (95% CI: 1.9– 7.4) more likely to have abnormal test results of liver function compared with placebo. The results of this systematic review support the reconsideration of recommendations to use paracetamol for these conditions. The study was published with an editorial and has received various prizes, including the BMJ 1st prize for the most accesses in 2015. The impact of withdrawing recommendations for paracetamol from clinical guidelines of low back pain is that the use of nonsteroidal anti-inflammatory drugs (NSAIDs), second line analgesic, is set to increase. A comprehensive review and appraisal of the literature on the efficacy and safety of NSAIDs was therefore paramount. Moreover, the effects of NSAIDs for some forms of spinal pain, such as acute low back pain and neck pain, remain uncertain. Chapter Five, therefore, presents a systematic review with meta-analysis of randomised placebo-controlled trials that aimed to determine the efficacy and safety of NSAIDs for low back pain, as well as neck pain, with or without radicular pain. Systematic searches were conducted in five large databases and 35 randomised trials were included in the review. Pain and disability outcomes were converted to a 0 to 100 scale, and a between-group difference of 10 points was used as the smallest worthwhile effect. Numbers needed to treat were also calculated providing the number of participants treated with NSAIDs who would achieve a clinically important pain reduction compared with placebo. Pooling revealed that for every six participants (95% CI: 4 to 10) treated with NSAIDs, only one would benefit from it, considering a between-group difference of 10 points (i.e., compared with placebo) for clinical importance in the short-term. Moreover, only in three of the 14 analyses looking at different types of spinal pain, outcomes, or time points were the pooled treatment effects marginally above our threshold for clinical importance. Additionally, taking NSAIDs increased the risk of developing gastrointestinal adverse events by 2.5 times (95% CI: 1.2–5.2). The initial management of low back pain usually focuses on conservative treatments, including analgesic medications. When conservative treatments are unsuccessful, surgery may be considered. Sciatica is a common indication for spine surgery, but at present the clinical course of this condition following surgery remains largely unknown. Therefore, the systematic review with meta-analysis of cohort studies presented in Chapter Six investigated the clinical course of pain and disability in patients who had surgery for sciatica. The searches were conducted in three large databases and 40 publications (39 cohort studies) were included. Pain and disability scores were converted to a common 0 to 100 scale and modelled as a function of time. Generalised estimating equations revealed that the pooled mean leg pain intensity before surgery was 75.2 (95% CI: 68.1 to 82.4) and the mean disability was 55.1 (95% CI: 52.3 to 58.0). Pooled mean leg pain (15.3, 95% CI: 8.5 to 22.1) and disability (15.5, 95% CI: 13.3 to 17.6) reduced substantially after three months. At five years, patients still reported moderate levels of leg pain (21.0, 95% CI: 12.5 to 29.5) and disability (13.1, 95% CI: 10.6 to 15.5). These findings suggest that patients with sciatica experience rapid improvements in the first three months after surgery, but are not likely to experience full recovery (i.e., absence of pain or disability) in the long-term. Lumbar spinal stenosis is the fastest-growing indication for spine surgery among older people. However, surgeons usually rely on their own preferences to decide on the best surgical technique for their patient. The systematic review and meta-analysis presented in Chapter Seven investigated the efficacy of surgery for lumbar spinal stenosis, and the effectiveness of various surgical options for this condition. The searches conducted on seven databases revealed limited evidence, as no surgical placebo-controlled trials were found. The 24 randomised trials included in the review compared various surgical options for lumbar spinal stenosis. Pain and disability scores were converted to a 0 to 100 scale. Pooling suggested that fusion offered no additional benefits over decompression surgery alone on pain (MD: –0.3, 95% CI: –7.3 to 6.7) or disability (MD: 3.3, 95% CI: –6.1 to 12.6). The interspinous process spacers alone were not more effective than conventional decompression in pain relief (MD: –0.6, 95% CI: –8.1 to 7.0) or disability reduction (MD: 1.3, 95% CI: –4.5 to 7.0), but showed small effects when compared with decompression plus fusion on disability (MD: 5.7, 95% CI: 1.3 to 10.0). This review was originally published in PLoS ONE in 2015, but has since then been updated and published in the Cochrane Database of Systematic Reviews, presented in this thesis as an appendix. The updated results provide current evidence on the surgical options for lumbar spinal stenosis, and could be used to guide clinical decision-making in this contentious area. Even though the effects of surgical procedures for patients with lumbar spinal stenosis remain unclear, the rates of fusion procedures have increased in the United States in recent times. It is unknown, however, whether these trends are happening elsewhere. Moreover, further information on complications could better inform surgeons, referring physicians, and patients about risks of surgical procedures. The population-based health record linkage study presented in Chapter Eight determined the trends in hospital admission and surgery for lumbar spinal stenosis in Australia, and investigated associated complications and health care use. The Centre for Health Record Linkage was used to link data of admissions, discharges, and transfers records from all public and private hospitals in New South Wales between 2003 and 2013. In one decade, the age-standardised rate of hospital admissions for lumbar spinal stenosis increased from 34.8 to 39.3 per 100,000 people. In 2013, the total costs for lumbar spinal stenosis were AU $46.1 million. Decompression rates increased from 19.0 to 22.1 per 100,000 people during 2003–2013, while the rates of simple fusion doubled, from 1.3 to 2.8 per 100,000 people. The most significant increase, however, occurred for complex fusion, from 0.6 to 2.4 per 100,000 people – a 4-fold increase in the same 10-year period. Mean hospital costs with decompression surgery were AU $12,168, while simple and complex fusion cost AU $30,811 and AU $32,350, respectively. Complex fusion procedures increased the odds of major complications by 4.1 (95% CI: 1.7–10.1) compared with decompression alone. This study confirms that in Australia the number of complex fusion procedures is increasing at a much faster rate than any other surgical procedure for lumbar spinal stenosis, though it is associated with increased risk of major complications and resource use. Overall, the studies presented in this thesis provide a substantial contribution to the understanding of the mechanisms and risk factors of low back pain. The identification of transient risk factors for persistent low back pain could help develop better preventive strategies. Although a great proportion of patients experience recovery within six weeks, it is now clear that a third is expected to have a recurrence, with multiple previous episodes being the only significant predictor of future recurrences. This thesis also contributes to a better understanding of current management strategies for low back pain. Paracetamol is ineffective for acute low back pain, but NSAIDs provide small effects in pain relief and disability reduction. Recommendations in clinical practice guidelines on pharmacological interventions should be reviewed. Although patients refractory to conservative treatments are frequently referred to surgery, the postoperative clinical course of sciatica is not as favourable as previously thought. Furthermore, despite the lack of evidence on surgical options for lumbar spinal stenosis, fusion surgery is increasing at an alarming rate in Australia.

This thesis begins with an overview of low back pain and sciatica epidemiology, including their characteristics, potential consequences, and management options. Additionally, twin studies are introduced and described as an emerging field of the genetic influence on spinal pain, with this methodology potentially providing more valid associations than traditional observational studies. The paucity of randomised controlled trials for low back pain within a twin population is also explored. The thesis concludes with a summary of findings and possible implications. The efficacy of interventions for sciatica is investigated in two systematic reviews, with the first review highlighting the superior, short-term effects for surgery over physical activity interventions, however these superior effects diminishing over time. The second review showed that structured exercise was superior to advice to remain active in the short-term management of sciatica, but no differences were observed in the long-term. In addition to these reviews, a short, structured commentary of a review of acupuncture is presented and showed potential for the effective management of sciatica. This thesis also utilised a discordant twin study design, enabling the examination of possible causal relationships between low back pain and various comorbidities, including early mortality. Although small associations were found between chronic low back pain and coronary heart disease, depression or anxiety symptoms in middle-aged twins, a causal path could not be elucidated. Despite an association, no causal link between spinal pain and early mortality (including cardiovascular-specific mortality) could be established in older twins aged ≥ 70 years. Finally, conducting a pilot randomised control trial within a twin study setting for the management of low back pain via sleep improvement is feasible; however lessons learnt during study recruitment and implementation suggest that modifications are required.

Musculoskeletal physiotherapy is the most common intervention for chronic low back disorder. Any observation on clinical practice or investigation into the clinical and scientific literature indicates that musculoskeletal physiotherapy encompasses a plethora of treatment modalities and approaches. The aim of the present investigation was to determine the most common intervention(s) that comprise musculoskeletal physiotherapy and to critically explore their empirical therapeutic basis. Two components were highlighted as the most frequently employed interventions; namely manually applied therapy (manual therapy) and exercise(s) to rehabilitate the lumbar spine's stabilising system. In the course of an extensive literature search, work was uncovered that suggested that the mechanisms required for spinal stability could be better facilitated using methods other than those in current clinical use. These discoveries culminated in the creation of a ten-week rehabilitation programme which was primarily developed to facilitate rehabilitation of spinal stabilisation but also permitted an empirical analysis of this component of musculoskeletal physiotherapy. The efficacy of the regime was then assessed in comparison to manual therapy and to a control (an education booklet) in a randomised controlled trial. Following a series of pilot studies, 300 patients with chronic low back disorder were randomly assigned to groups and completed their respective management programmes. Data were collected on pain, disability, handicap, impairment and quality of life prior to entry and at three, six, twelve and twenty-four months post intervention. The results indicated a consistent trend for greater improvement in the spinal stabilisation group in the pain, handicap, impairment, disability, dysfunction and medication variables. These trends reached statistical significance at the three-month follow-up stage as evidenced by quality of life (P = 0.025), at the six-month follow-up stage in pain (P = 0.009) and dysfunction (P = 0.042) and at the one-year follow-up stage in medication (P = 0.007), dysfunction (P = 0.048), disability (P = 0.0098) and quality of life (P = 0.003). It was therefore concluded that the spinal stabilisation programme was a more effective component of musculoskeletal physiotherapy (when analysed in isolation) than manually applied therapy or an education booklet in the management of chronic low back disorder. Various sub-analyses of the data were conducted. Subjects who entered the study with high levels of low back pain (greater than 50 numerical rating scale) demonstrated a statistically Significant reduction in pain levels (P = 0.04) in both the manual therapy group and the spinal stabilisation group in comparison to the education control group at the three-month follow-up stage. These data provide empirical evidence towards the efficacy of these two musculoskeletal physiotherapy management regimes as being effective in pain reduction in comparison to an active control intervention. This has not hitherto been demonstrated on patients with chronic low back disorder.

This thesis was initiated by an awareness of the impact of low back pain in Western society in general and Australian society in particular. The studies and experiments in this thesis contribute towards an understanding of chiropractic as a professional entity in Victoria and the nature of its clinical practice. The issue of male adolescent LBP has been explored and in addition to an epidemiological description of this clinical entity, its anthropometric dimensions have been documented. The qualitative review of the literature provides ample justification for the management of patients with LBP by chiropractors, using manual or manipulative techniques. The observational study of the Victorian context in which chiropractors are educated, registered, and entitled to practice, demonstrates that Victorian chiropractors are appropriate providers of manipulative health care. They perform the role of primary contact, primary health care providers with diagnostic, treatment and management skills focussed mainly on musculoskeletal conditions, but with a small proportion of practice based in the health or preventive context, and are well placed to provide the manual and manipulative services required in the management of LBP patients. The profession is shown to have strategies in place to ensure continued legal and community acceptance. The strategies include those at entry level to the profession, such as the legislative provisions of government and the competencies required for registration as instilled during the professional education process, and those which are more of the nature to maintain the integrity of professional practice, such as the " standards of practice" concept. These are important characteristics given it is shown that the Victorian chiropractic profession is not homogenous with respect to educational standards, has a disparate gender balance, the presence of a few non-registered 'chiropractors', and a disparity in utilisation patterns with a significant tail to the right. However the chiropractic profession is shown to hold a position of strength and leadership in the Australian context with respect to the provision of manipulative health care. Indeed, it could be said that chiropractors are at the leading edge of the quality process with respect to the provision of manipulative health care in Australia. The description of chiropractic practice shows a patient base of all ages, including adolescents, presenting with a range of possible diagnoses, often funded by a third party, and with a high proportion of return visits suggestive of patient compliance and satisfaction. It is convincingly demonstrated that persons with work-related LBP attend to chiropractors in Victoria and are effectively managed with the aim being the restoration of optimal spinal function and, in the case of work-injured patients, an early return to work. This thesis includes utilisation data which suggest only a minority of Victorian chiropractors practice outside the responsible parameters described above. The case-mix data and patient profiles presented in this thesis are congruent and complement each other, suggesting a high level of patient satisfaction indicated by the high proportion of return visits by regular patients and a faster, return-to-work by work-injured claimants. The point and sample prevalence of LBP in a population of suburban male adolescents is described and shown to be similar to those found in comparable Western societies. The data for a sample of traditional Australian male adolescents describes the LBP experience for the first time in such a population and emphasises the wide variance between societies which is now being identified in the literature. The LBP experience of a typical suburban Australian male adolescent is identified and described in terms of chronicity, frequency and episode duration. Typically the male adolescent with LBP has a chronic (> 90 d) problem with frequent episodes of pain (from 2 or 3 times a month to 2 or 3 times week) which last a few hours. The pain is a little limiting but allows the performance of the Activities of Daily Living. While some limitation of general sporting activity due to pain is experienced, school attendance is generally not compromised. A particular clinical instrument, the Metrecom computerised electro-goniometer, is studied and found to be appropriate for use in gathering anthropometric dimensions to test hypotheses relating to an association between anthropometric dimensions and LBP in a male adolescent population. The applied level of uncertainty of the instrument is within acceptable limits for these dimensions. The anthropometric study tests the broad null hypothesis that the mean of specific anthropometric dimensions would be equal among samples of male adolescents drawn from the Australian population. The actual groups are a Melbourne 'Pain' group, a Melbourne 'No Pain' group, and a 'Traditional No Pain' group. The pain group reported either current LBP or a positive history of LBP, while the 'no pain' groups denied either current or historical LBP. The alternate hypothesis will be shown to be proven for the dimensions 'sitting height', 'upper body' length, 'pelvic height', and the ratio of the 'upper:lower' body segment in a population of male adolescents with idiopathic or mechanical LBP. This thesis meets its objectives of describing the chiropractic profession and its practise in the Victorian context, demonstrates the prevalence of LBP in a male adolescent population, and identifies particular anthropometric dimensions associated with those who report a LBP experience. The fact that a number of anthropometric dimensions are detectable in adolescence may allow the development of appropriate screening programs which in turn may lead to the design and introduction of suitable prophylactic interventional programs for persons found to be potentially prone to idiopathic or mechanical LBP, at the least reducing the severity and at most reducing the onset of this expensive problem in adulthood. The ratio of the upper body segment to the lower body segment would appear to be most appropriate indicator; it is robust in that it is a prime dimension, easily accessible, and with a low level of measurement uncertainty. Most importantly it would appear to hold validity throughout adolescence as it does not have a linear relationship with age.