Dissertations / Theses on the topic 'Back pain'

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.

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.

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.

This PhD advances knowledge on breast size as a factor associated with upper back pain in mature-aged women. Using cross-sectional and prospective study designs involving mature-aged women and women undergoing reduction mammoplasty, self-reported aspects of health and psychological wellbeing and physical characteristics were measured and examined in relation to breast size and upper back pain. The aim of this thesis was to investigate the relationship between breast size and upper back pain in mature-aged women.

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 thesis aims to investigate pharmacological and surgical treatment for low back pain and postoperative pain. Chapter Two investigates the efficacy and safety of antibiotics for people with low back pain. In people with Modic type I changes and disc herniation, oral amoxicillin probably had a small effect in reducing back pain and a moderate effect in improving disability in the short term, compared to placebo. Chapter Three provides an overview of low back pain in China, the most populous country, where low back pain is a leading and growing disease burden. Challenges faced in managing low back pain in China include the fragmented healthcare system, lack of national data, and inequalities in access to healthcare. Chapters Four and Five report on the design and progress of a randomised placebo-controlled trial investigating the efficacy and safety of oral glucocorticoids for people with sciatica. Recruitment has been impacted by the Covid-19, necessitating protocol changes such as adding social media campaign and introducing telehealth. Chapter Six determines the efficacy and safety of surgery compared to non-surgical treatment for sciatica due to lumbar disc herniation. Discectomy may be superior to non-surgical treatment in reducing leg pain and improving disability, but the benefits declined over time, with no effect observed one year after surgery. Chapter Seven determines the efficacy and safety of opioids compared to placebo or non-opioid analgesics, provided upon discharge after surgery. Opioid analgesics, compared to non-opioid analgesia, did not reduce postoperative pain after surgical discharge at all time points within one year. Opioid analgesics increased the risk of adverse events. Together these studies address gaps in antibiotic treatment for low back pain, overview of low back pain in China, surgical treatment for sciatica, and opioid analgesia after surgical discharge.

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 main aim of this thesis was to gain a better understanding of cultural influences on pain-related beliefs among Australian Indian migrants. This was achieved through a series of studies. First, existing community-based approaches to, and outcomes of, chronic musculoskeletal health conditions were examined in a systematic review. Although the quality of the evidence was low, there was some support for the effectiveness of education and exercise in the management of chronic musculoskeletal health conditions for rural and remote populations and use of community engagement strategies to ensure treatment success. The second study involved cross-cultural adaptation and validation of two beliefs questionnaires, Back Beliefs Questionnaire (BBQ) and Pain Self-Efficacy Questionnaire (PSEQ) in the Indian language of Marathi. This addressed the need for assessment tools that evaluate beliefs about pain to be adapted to the language and culture of Indian communities. Beliefs were examined in a cross-sectional questionnaire study among 386 Indian migrants living in Sydney using the BBQ. It was found that beliefs relating to back pain had subtle cultural elements, which warranted further investigation. These subtle cultural elements were further explored using focus groups in which Indian migrants living in Sydney provided a deeper understanding of the cultural beliefs relating to chronic back pain. Participants (n=26) in the focus group discussions identified a core cultural belief in ‘the philosophy of Karma’, and cultural values of collectivism-contribution, gendered roles, and mind-body wellness, as central to the experience of pain. The findings can be used to guide delivery of current approaches to back pain management using a Karmic lens, aligning with the beliefs held by Indian migrant communities. Collectively, these studies provide greater insight into the Indian cultural influences on pain-related beliefs.

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.

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.

BACKGROUND: Healthcare workers are among the most injured workers in the United States. This is due to the high rate of patient handling. The low back is the most injured in this population. This study observed biomechanical factors and how these factors affect low back and ground reaction forces. This study further investigated pain and its relationship to low back force, multifidus cross-sectional area, and multifidus activation in healthcare workers. METHODS: The 45 participants included 10 healthy subjects in the preliminary study and 35 active healthcare workers in the main study. Subjects filled out the VAS to determine current pain level. Ultrasound images of the multifidus muscles were taken. The participants were fitted with reflective markers and surface EMG sensors. A series of patient transfers at various bed heights using three different transfer devices was undertaken. The transfer devices included a Cotton sheet, a Skil-Care™ Transfer Sling, and an AirPal® device. RESULTS: There was a downward trend in resultant low back force when comparing lower bed heights to higher. Therefore, the highest bed position was determined to be optimal. There were significant differences in low back force between self-chosen and optimal bed heights among healthcare workers. There was no significant difference between peak low back or ground reaction forces between pain and nonpain groups. There was a significant difference in multifidus cross-sectional area between these groups at S1, a trend toward significance at L5, and no difference at L4. There was a trend toward significance when comparing multifidus activation between these groups as recorded by surface EMG. CONCLUSIONS: Healthcare workers should choose higher bed heights and appropriate equipment to reduce low back force and those who have smaller multifidus have more pain.

This thesis presents an account of a sociological research project exploring the field of Chronic Back Pain (CBP). This medical condition, despite being prevalent worldwide, is extremely problematic and difficult to treat because of its often ambiguous medical status and fluctuating symptoms. These problems of diagnosis and resolution often have a negative impact on sufferers’ daily lives, social relationships, identity and sense of self, and are often characterised by negative encounters with medical professionals. This study explores these themes via academic work from the field of cultural sociology, and in particular, from the French pragmatic approach. My data is analysed via Lamont’s (1992) theory of ‘symbolic boundary making’ and other related work on boundaries. I also utilize work on accounts to explore respondents’ processes of account-making. In addition, I use Gieryn’s (1983) model of ‘boundary-work’ to explore the issues of professional identity and the professional struggles that are apparent in the practitioners’ accounts. The research was carried out using qualitative methods. In total, I conducted forty in-depth semi-structured interviews with patients with CBP, GPs, physiotherapists, chiropractors, osteopaths, and an acupuncturist.

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.

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.

The thesis describes a number of qualitative and quantitative studies in the investigation of psychosocial risk factors for back pain and absenteeism. A study of information processing 'biases' was completed comparing three diagnostically different chronic pain groups. Back pain and arthritis patients devote greater processing resources towards illness information than healthy controls. Development of a pain schema is suggested to be related to the personal meaning of pain. A further cross sectional investigation of psychosocial factors associated with back pain in a care assistant population was conducted. Work factors including perception of physical strain and job satisfaction; psychological factors such as pain beliefs, emotionality and family pain history and measures of pain in the last month were assessed. Results found that people reporting back pain had significantly lower job satisfaction, were older and worked significantly longer as care assistants than those reporting a mixture of pain symptoms. Reporting of general pain symptoms and absenteeism was also investigated. This was followed by a longitudinal study of care workers at risk of back pain. Negative emotionality and job satisfaction were identified in a logistic regression as being significant predictors of back pain at six months. High negative emotionality scores at baseline were significantly correlated with high numbers of pain symptoms at follow-up. Difficulties in conducting longitudinal risk research are discussed. The development of the pain schema was investigated by distributing word stem tasks to a variable pain population at baseline and follow-up. People reporting three or more pain symptoms and high pain frequencies were more likely to give higher pain sensory completions. At follow-up, as number of pain symptoms increased over six months so did the number of pain affective responses. The final study was a qualitative investigation of the meaning of back pain in thirty two care assistants using semi structured interviews. Findings suggest that patients delay seeking treatment when they perceive high susceptibility of back pain in the iii working environment, low severity of back pain and few benefits of treatment. Such findings are further discussed within the principals of the Health Belief Model (Becker, 1974).

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.

There is currently little primary data looking at the epidemiology of back pain in older people and there are few large-scale population based studies which consider the occurrence or aetiology of back pain within this age group. Some evidence suggests that while non-disabling back pain decreases in the oldest old, the prevalence of disabling back pain may continue to increase. However, the aetiology of back pain in this group remains relatively unknown. Therefore, the overall aim of the current thesis was to investigate the epidemiology of back pain in older people, to examine the occurrence of back pain and age-related patterns in prevalence and incidence (descriptive epidemiology) and to identify potential risk factors for predicting back pain onset in those ≥75 years, specifically, to determine the role of social networks (analytical epidemiology). This was done through secondary analysis of a prospective cohort study from Cambridge looking at older people ≥75 years. It has been shown that while the prevalence of non-disabling back pain did not vary significantly across age, the prevalence of disabling back pain increased with age. In addition, it has been demonstrated, firstly, that aspects and indicators of physical health and a prior history of back pain are associated and independent predictors of back pain in older people; and secondly, that while objective measures of social contact are not risk markers for back pain, low mood, feelings of social isolation and depression are more strongly associated. These findings were further verified and confirmed in a second study, a cross-sectional survey of people ≥65 years living in rural Scotland. It can therefore be concluded that back pain is a common problem in the older population and, while mild back pain may remain constant across older age, disabling back pain continues to increase into the oldest old. The risk profile for back pain in older age is multifactorial, while some risk factors evident in younger populations remain; there is greater emphasis on the impact of mood and psychosocial factors.

Low back pain has long been estimated to be the most prevalent and debilitating source of chronic pain. The present study first reviews the literature addressing the various theories of pain, the physiological and psychological variables important in pain research, and the psychotherapeutic approaches that have been used to date to reduce pain. Thirty-seven hospitalized chronic back pain patients were administered the cold-pressor test and a medical pain stimulus procedure which was medically relevant to their back pathology. A card-sort method was utilized in order to assess the coping strategies employed by the patients during these two pain stimulus tasks. These procedures were repeated following treatment. Coping strategies used by patients during the two pain tasks were compared. Results demonstrated that there was a significant difference in the manner in which patients coped with the two types of pain. Cold-pressor measures of pain threshold and tolerance were not significantly different between pretreatment and post-treatment. These measures were also not positively correlated with treatment outcome. A multiple regression approach demonstrated that particular coping strategies were significantly predictive of treatment outcome. The medical pain stimulus procedure was found to provide more significant pedictor variables than the cold-pressor test. At pre-treatment assessment, patients who relied on dramatized coping strategies were less likely to be successful in treatment. Breathing activity and pain acknowledgement were positive coping techniques highly predictive of successful outcome in this study. The use of computers for assessment and other recommendations for future research were discussed.

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.

Redesigning how care is structured and delivered has been identified as a potential solution to enable implementation of best practice care for back pain. Redesigning care requires a deep understanding of local needs and context, and participation of stakeholders in the process to promote relevance, acceptance, and uptake. This thesis includes studies that have contributed toward defining the problem, identifying potential solutions, and proposing a new service to improve care for people with chronic back pain. The aim of the thesis was to complete the design phase of a new service for chronic back pain in a hospital setting. This thesis used different methods of research to conduct needs assessment and service design guided by an intervention mapping approach. Needs assessment was conducted through quantitative and qualitative evaluations of current care (Chapter 2 and Chapter 3). Service design was undertaken by creating a logic model of the health problem and a logic model of change, and identifying key components of a new service using information from the needs assessment and stakeholder feedback (Chapter 4, Chapter 5, and Chapter 6). As part of service design, a feasibility study protocol was designed to test key components of a new service for chronic back pain (Chapter 7). The needs assessment studies demonstrated that current service delivery is largely not structured to provide patients with timely and coordinated, long-term management. Whilst the clinical record review showed that existing practice involved good uptake of guideline recommendations, the focus groups and interviews suggested that many patients might be disengaging due to misaligned care expectations and a pathoanatomical focus. The service design process with stakeholder participation showed overall agreement with the needs assessment findings and proposed key components of a new service. This participatory process also revealed potential barriers related to clinician sensitivities and challenges with reimagining traditional roles which could adversely impact progress in the next steps of the service development process. This thesis has contributed to achieving the aim of completing the design phase of a new service for chronic back pain in a hospital setting. Moreover, this thesis provided new insights into the structures and processes that would need to be created to enable and support best practice care for chronic back pain.

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.

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.