Contemporary low back pain research - and implications for practice

RESUME-1: a Phase III study of tolperisone in the treatment of painful, acute muscle spasms of the back

Tolperisone is a nonopioid, centrally acting muscle relaxant in clinical development in the USA for the treatment of symptoms associated with acute, painful muscles spasms of the back. CLN-301, RESUME-1, is a 14-day double-blind, randomized, placebo-controlled, parallel-group Phase III study of the efficacy and safety of tolperisone administered orally three-times daily in 1000 male and female subjects at approximately 70 clinical sites in the USA experiencing back pain due to or associated with muscle spasm of acute onset. Tolperisone is a promising therapeutic for managing acute, painful muscle spasms of the back as it appears to lack the off-target CNS effects often seen with conventional skeletal muscle relaxants. Clinical Trials Registration: NCT04671082.

Patients' Views on the Implementation Potential of a Stratified Treatment Approach for Low Back Pain in Germany: A Qualitative Study

Stratified care for low back pain (LBP) has been shown to be clinically- and cost-effective in the UK, but its transferability to the German healthcare system is unknown. This study explores LBP patients’ perspectives regarding future implementation of stratified care, through in-depth interviews (n = 12). The STarT-Back-Tool was completed by participants prior to interviews. Interview data were analysed using Grounded Theory. The overarching theme identified from the data was ‘treatment-success’, with subthemes of ‘assessment and treatment planning’, ‘acceptance of the questionnaire’ and ‘contextual factors’. Patients identified the underlying cause of pain as being of great importance (whereas STarT-Back allocates treatment based on prognosis). The integration of the STarT-Back-Tool in consultations was considered helpful as long as it does not disrupt the therapeutic relationship, and was acceptable if tool results are handled confidentially. Results indicate that for patients to find STarT-Back acceptable, the shift from a focus on identifying a cause of pain and subsequent diagnosis, to prediction-orientated treatment planning, must be made clear. Patient ‘buy in’ is important for successful uptake of clinical interventions, and findings can help to inform future strategies for implementing STarT-Back in the Germany, as well as having potential implications for transferability to other similar healthcare systems.

Identifying patients with chronic pain who respond to acupuncture: results from an individual patient data meta-analysis

BACKGROUND

In a recent individual patient data meta-analysis, acupuncture was found to be superior to sham and non-sham controls in patients with chronic pain. It has been suggested that a subgroup of patients has an exceptional response to acupuncture. We hypothesized the presence of exceptional acupuncture responders would lead to a different distribution of pain scores in acupuncture versus control groups, with the former being skewed to the right.

METHODS

This individual patient data meta-analysis included 39 high-quality randomized trials of acupuncture for chronic headache, migraine, osteoarthritis, low back pain, neck pain and shoulder pain published before December 2015 (n = 20,827). In all, 25 involved sham acupuncture controls (n = 7097) and 25 non-acupuncture controls (n = 16,041). We analyzed the distribution of change scores and calculated the difference in the skewness statistic-which assesses asymmetry in the data distribution-between acupuncture and either sham or non-acupuncture control groups. We then entered the difference in skewness along with standard error into a meta-analysis.

FINDINGS

Control groups were more right-skewed than acupuncture groups, although this difference was very small. The difference in skew was 0.124 for non-acupuncture-controlled trials (p = 0.047) and 0.141 for sham-controlled trials (p = 0.029). In a pre-specified sensitivity analysis excluding three trials with outlying results known a priori, the difference in skew between acupuncture and sham was no longer statistically significant (p = 0.2).

CONCLUSION

We did not find evidence to support the notion that there are exceptional acupuncture responders. The challenge remains to identify features of chronic pain patients that can be used to distinguish those that have a good response to acupuncture treatment.

Early Return to Work Has Benefits for Relief of Back Pain and Functional Recovery After Controlling for Multiple Confounds

OBJECTIVE

The aim of the study was to evaluate the effect on health outcomes of an early or immediate return-to-work (RTW) after acute low back pain (LBP).

METHODS

A longitudinal cohort of workers (N = 557) consulting for uncomplicated LBP were assessed on demographic, pain, occupational, and psychosocial variables. Pain and function were assessed at 3-month postpain onset. We tested the longitudinal effects of an early RTW on 3-month outcomes.

RESULTS

Pain and function improved more rapidly for workers with an immediate (30.7%) or early (1 to 7 days) RTW (36.8%). Eleven demographic, health, or workplace variables were identified as potential confounds, but controlling for these factors only partially attenuated the benefits of an early RTW.

CONCLUSIONS

An early RTW improves acute LBP and functional recovery, and alternate confounding explanations only partially eclipse this therapeutic effect.

"Selling" chronic pain: physiotherapists' lived experiences of communicating the diagnosis of chronic nonspecific lower back pain to their patients

Introduction: Chronic nonspecific lower back pain (CNSLBP) is a common musculoskeletal condition which can be a source of significant distress and disability for patients. Approaches to managing CNSLBP have been explored in healthcare literature, as has the importance of communication in physiotherapy practice. However, no previous studies have explored clinicians' experiences of communicating their understanding of this diagnosis to their patients.Methods: A qualitative research design, using hermeneutic phenomenological methodology, was employed. Five participants were purposively recruited for the research and data collected via semi-structured interviews. Interpretative phenomenological analysis (IPA) methods were used to analyze the data. Emergent, super-ordinate and master themes were developed to help convey the qualitative significant meanings of the lived-through experiences.Findings: Three master themes were identified, with each comprising two sub-themes. These were: 1) Patient-centeredness (1a. Understanding the patient; and 1b. emotional awareness and adaptability); 2) Getting patients "on board" (2a. the "selling" process; and 2b. paternalism and the clinician's perspective); and 3) Dealing with conflict and uncertainty (3a. fear of interpersonal conflict; and 3b. personal doubts and uncertainty).Conclusions: Personal conflicts were identified between clinicians' descriptions of their wishes to "sell" their own perspectives to patients while simultaneously wanting to demonstrate a patient-focused approach and avoid the interpersonal conflicts which arose from clashes with patients' beliefs. Building a good initial rapport, showing empathy and adapting approaches in response to perceptions of patients' reactions were perceived as strategies to help mitigate the risks of failed communication, but this was something for which participants felt unprepared by their prior training.

Decision support tools in low back pain

Information from individual classification systems or clinical prediction rules that aim to facilitate stratified care in low back pain is important but often not comprehensive enough to be used to support clinical decision-making. The development and implementation of a clinically useful decision support tool (DST) that considering all key features is a challenging enterprise, requiring a multidisciplinary approach. Key features are inclusion of all relevant treatment options, patient characteristics, and benefits and harms and presentation as an accessible and easy to use toolkit. To be of clinical value, a DST should (1) be based on large numbers of high-quality data, allowing robust estimation of benefits and harms; (2) be presented using visually attractive and easy-to-use software; (3) be externally validated with a clinical beneficial impact established; and (4) include a procedure for regular updating and monitoring. As an illustration, we describe the development; presentation; and plans for further validation, implementation, and updating of the Nijmegen Decision Tool for Chronic Low Back Pain (NDT-CLBP).

Evaluation of a rolling rehabilitation programme for patients with non-specific low back pain in primary care: an observational cohort study

AIM

The Back Rehabilitation Programme (BRP) is a group exercise programme for patients with non-specific low back pain (NSLBP) that combines cognitive behavioural therapy principles and therapeutic exercise to empower patients to self-manage their condition. Poor attendance and high attrition rates resulted in changes to the format of the programme from a standard sequential approach to a continual rolling approach. The aim of this study was to evaluate the effectiveness of this new approach on patient outcomes and its impact on attendance rates.

METHOD

A service evaluation, using a retrospective, observational cohort design, of all patients with NSLBP who attended the BRP during a 12-month period was undertaken. Outcome measures used were as follows: Bournemouth Questionnaire (BQ); fitness tests: sit to stand test, step test and walk test (taken at baseline and post programme); and attendance (taken post programme).

RESULTS

Of the patients, 56% had an improved BQ score ≥ 47%, indicating a clinically significant change. Inferential testing showed statistically significant improvements in the BQ and all three fitness tests post programme (P< 0.0001). In total, 62 patients attended the rolling BRP, and 41 patients (66%) completed. Thus, the percentage of patients completing the new programme had doubled compared with the original standard programme.

CONCLUSION

Patients with NSLBP who attended the continual rolling BRP show clinical and statistical improvements. The rolling format also appeared to enhance patient attendance. As such, the rolling BRP should be considered by practitioners as an effective management strategy when treating patients with NSLBP.

Efficiency of three treatment strategies on occupational and quality of life impairments for chronic low back pain patients: is the multidisciplinary approach the key feature to success?

OBJECTIVE

To compare the effectiveness of three treatment strategies for chronic low back pain with varying biomechanical intensity and multidisciplinary approach.

METHODS

A monocentric randomized controlled trial with a 12-months follow-up, conducted in the French Valley Loire region from May 2009 to April 2013. Participants were working-aged patients with chronic low back pain referred to a French chronic low back pain care-network to support medical and occupational issues. Three treatment strategies, each for five weeks were compared: (i) intensive and multidisciplinary program conducted in a rehabilitation center; (ii) less intensive outpatient program conducted by a trained private physiotherapist; (iii) mixed strategy combining the same outpatient program associated with a weekly multidisciplinary intervention. The effects of treatment conditions were compared using an "intention to treat" approach: Number of days' sick leave during the 12-months following treatment, and quality of life and social ability assessed by auto-questionnaires.

RESULTS

A total of 159 patients (58.9% men, 41.5 ± 10.3 years old, median duration of sick leave = 221.0 days (127.5-319.0)) were included. Sick leave duration significantly decreased during the 12-months following treatment in the three groups. There was no significant difference for the evolution of participants' quality of life, social ability, and personal beliefs between the three groups.

CONCLUSION

This study confirms that disparate treatments might show similar effectiveness because they could all work through concomitant changes in beliefs, attitudes, and coping mechanisms. The original mixed strategy can treat a larger number of chronic low back pain patients, at a lower cost and provide local community-based care.

CLINICAL TRIAL REGISTRATION

NCT02030171.

Mechanical Low Back Pain: Secular Trend and Intervention Topics of Randomized Controlled Trials

PURPOSE

To evaluate the number of published randomized controlled trials (RCTs) focusing on mechanical low back pain (MLBP) rehabilitation, the secular (i.e., long-term) trend, and the distribution of interventions studied.

METHODS

All included RCTs were extracted from all Cochrane systematic reviews focusing on rehabilitation therapies for MLBP, and two independent reviewers screened and analyzed the information on interventions.

RESULTS

After removal of duplicates, the data set consisted of 196 RCTs published between 1961 and 2010. The number of RCTs published increased consistently over time: 2 trials (1% of the total) were published in 1961-1970, 10 (5%) in 1971-1980, 41 (21%) in 1981-1990, 68 (35%) in 1991-2000, and 75 (38%) in 2001-2010. The intervention of interest in the majority of RCTs was exercise therapy (115/399; 29%), followed by spinal manipulation therapies (60/399; 15%).

CONCLUSION

The number of RCTs focusing on MLBP has risen over time; of all interventions studied, exercise therapy has attracted the most research interest.

Back pain: Prevention and management in the workplace

Despite all the efforts in studying work-related risk factors for low back pain (LBP), interventions targeting these risk factors to prevent LBP have no proven cost-effectiveness. Even with adequate implementation strategies for these interventions on group level, these did not result in the reduction of incident LBP. Physical exercise, however, does have a primary preventive effect on LBP. For secondary prevention, it seems that there are more opportunities to cost-effectively intervene in reducing the risk of long-term sickness absence due to LBP. Starting at the earliest moment possible with proper assessment of risk factors for long-term sickness absence related to the individual, the underlying mechanisms of the LBP, and also factors related to the workplace by a well-trained clinician, may increase the potential of effective return to work (RTW) management. More research on how to overcome barriers in the uptake of these effective interventions in relation to policy-specific environments, and with regard to proper financing of RTW management is necessary.

Clinical challenges of classification based targeted therapies for non-specific low back pain: What do physiotherapy practitioners and managers think?

Background

Classification of non-specific low back pain (NSLBP) was recommended to better target care and so maximise treatment potential. This study investigated physiotherapy practitioners' (PPs) and managers' (PMs) views, experiences and perceptions of barriers and enablers for using classification systems (CSs) to better target treatment for NSLBP in the NHS primary care setting.

Design

Qualitative focus group and interviews.

Methods

Data from semi-structured interviews of three PMs and a focus group with five PPs, considered local opinion leaders in physiotherapy, was thematically analysed.

Results

Five themes emerged (i) CS knowledge: PPs and PMs were aware of CSs and agreed with its usefulness. PPs were mostly aware of CSs informing specific treatments whilst PMs were aware of prognosis based CSs. (ii) Using CSs: PPs classify by experience and clinical reasoning skills, shifting between multiple CSs. PMs were confident that evidence-based practice takes place but believed CSs may not be always used. (iii) Advantages/disadvantages of CSs: Effective targeting of treatments to patients was perceived as advantageous; but the amount of training required was perceived as disadvantageous. (iv) Barriers: Patients' expectations, clinicians' perceptions, insufficiently complex CSs, lack of training resources. (v) Enablers: Development of sufficiently complex CSs, placed within the clinical reasoning process, mentoring, positive engagement with stakeholders and patients.

Conclusions

PPs and PMs were aware of CSs and agreed with its usefulness. The current classification process was perceived to be largely influenced by individual practitioner knowledge and clinical reasoning skills rather than being based on one CS alone. Barriers and enablers were identified for future research.

Chronic low back pain sufferers exhibit freezing-like behaviors when asked to move their trunk as fast as possible

BACKGROUND CONTEXT

The effect of chronic low back pain (CLBP) on the kinematic parameters of trunk motion has received much more interest in this last decade. However, there are no descriptions of the motor strategies that occur when patients perform trunk movements in the three anatomical planes at different pace conditions.

PURPOSE

To investigate motor strategies used by CLBP patients and asymptomatic people while performing different go and back trunk movements in an upright standing position.

STUDY DESIGN

A comparative study.

PATIENT SAMPLE

The control group (CG, n=33) included 14 men and 19 women with no history of low back pain, and the chronic low back pain group (CLBPG, n=49) included 21 men and 28 women.

OUTCOME MEASURES

Kinematic data were analyzed during six trunk movements: flexion, extension, left and right lateral bendings, and rotations under two pace conditions (preferred and fast paces).

METHODS

A three-dimensional optoelectronic motion analysis system was used to assess static (trunk inclinations and base of support) and dynamic (range of motion [ROM] and mean angular velocity of the trunk) parameters during the go and back phases of trunk movements.

RESULTS

In the initial position, CLBPG showed a more forward-tilted trunk inclination (2.1°±1.1°, p=.013) compared with CG. The base of support was significantly higher in CG (+22.7 cm2, p=.009) during the fast pace when compared with the preferred pace. Regardless of the pace condition, ROM and mean angular velocity of the trunk were significantly lower in CLBPG for all examined movements and the pace condition did not significantly alter ROM. At the preferred pace, both groups displayed the same motor strategy: they all went faster during the second phase of movement than during the first phase. However, at the fast pace, while CG was going faster during the first phase than during the second, CLBPG maintained the same motor strategy as at the preferred pace.

CONCLUSIONS

Contrary to CG who changed its motor behavior from a preferred pace to a fast pace, CLBPG exhibited freezing-like behaviors. This original result highlights the importance of studying the velocity. The use of this parameter may improve the diagnosis of CLBP patients and could be a key indicator for treatment progress and long-term monitoring.

Indications, benefits, and risks of Pilates exercise for people with chronic low back pain: a Delphi survey of Pilates-trained physical therapists

BACKGROUND

The effectiveness of Pilates exercise for treating people with chronic low back pain (CLBP) is yet to be established. Understanding how to identify people with CLBP who may benefit, or not benefit, from Pilates exercise and the benefits and risks of Pilates exercise will assist in trial design.

OBJECTIVES

The purpose of this study was to establish a consensus regarding the indications, contraindications, and precautions of Pilates exercise and the potential benefits and risks of Pilates exercise for people with CLBP.

METHODS

A panel of 30 Australian physical therapists experienced in the use of Pilates exercise were surveyed using the Delphi technique. Three electronic questionnaires were used to collect participant opinions. Answers to open-ended questions were analyzed thematically, combined with research findings, and translated into statements about Pilates exercise. Participants then rated their level of agreement with statements using a 6-point Likert scale. Consensus was achieved when 70% of panel members agreed or disagreed with an item.

RESULTS

Thirty physical therapists completed the 3 questionnaires. Consensus was reached on 100% of items related to the benefits, indications, and precautions of Pilates exercise, on 50% of items related to risks, and on 56% of items related to contraindications. Participants agreed that people who have poor body awareness and maladaptive movement patterns may benefit from Pilates exercise, whereas those with pre-eclampsia, unstable spondylolisthesis, or a fracture may not benefit. Participants also agreed that Pilates exercise may improve functional ability, movement confidence, body awareness, posture, and movement control.

LIMITATIONS

The findings reflect the opinions of only 30 Australian physical therapists and not all health professionals nationally or internationally. These findings, therefore, need to be verified in future research trials.

CONCLUSIONS

These findings contribute to a better understanding of the indications, contraindications, and precautions of Pilates exercise and the benefits and risks of Pilates exercise for people with CLBP. This information can assist in design of future trials examining the effectiveness of Pilates exercise.

Stratified models of care

Stratified care for back pain involves targeting treatment to subgroups of patients based on their key characteristics such as prognostic factors, likely response to treatment and underlying mechanisms. It aims to tailor therapeutic decisions in ways that maximise treatment benefit, reduce harm and increase health-care efficiency by offering the right treatment to the right patient at the right time. From being called the 'Holy Grail' of back pain research over a decade ago, stratified care is becoming the zeitgeist in research and clinical practice. In this chapter, we introduce and evaluate the quality and underpinning evidence for three examples of stratified care for back pain to highlight their general principles, research design issues and clinical practice implications. We include consideration of their merits for implementation in practice. We conclude with a set of remaining, key research questions.

Consumers' experiences of back pain in rural Western Australia: access to information and services, and self-management behaviours

Background

Coordinated, interdisciplinary services, supported by self-management underpin effective management for chronic low back pain (CLBP). However, a combination of system, provider and consumer-based barriers exist which limit the implementation of such models into practice, particularly in rural areas where unique access issues exist. In order to improve health service delivery for consumers with CLBP, policymakers and service providers require a more in depth understanding of these issues. The objective of this qualitative study was to explore barriers experienced by consumers in rural settings in Western Australia (WA) to accessing information and services and implementing effective self-management behaviours for CLBP.

Methods

Fourteen consumers with a history of CLBP from three rural sites in WA participated. Maximum variation sampling was employed to ensure a range of experiences were captured. An interviewer, blinded to quantitative pain history data, conducted semi-structured telephone interviews using a standardised schedule to explore individuals’ access to information and services for CLBP, and self-management behaviours. Interviews were digitally recorded and transcribed verbatim. Inductive analysis techniques were used to derive and refine key themes.

Results

Five key themes were identified that affected individuals’ experiences of managing CLBP in a rural setting, including: 1) poor access to information and services in rural settings; 2) inadequate knowledge and skills among local practitioners; 3) feelings of isolation and frustration; 4) psychological burden associated with CLBP; and 5) competing lifestyle demands hindering effective self-management for CLBP.

Conclusions

Consumers in rural WA experienced difficulties in knowing where to access relevant information for CLBP and expressed frustration with the lack of service delivery options to access interdisciplinary and specialist services for CLBP. Competing lifestyle demands such as work and family commitments were cited as key barriers to adopting regular self-management practices. Consumer expectations for improved health service coordination and a workforce skilled in pain management are relevant to future service planning, particularly in the contexts of workforce capacity, community health services, and enablers to effective service delivery in primary care.

Pathoanatomy and classification of low back disorders

Over the past decade research into the effectiveness of low back disorders (LBDs) has focused on the classification of subgroups more likely to respond to specific treatment. Much of this research has explicitly excluded a focus on pathoanatomical factors based on a questionable interpretation of the biopsychosocial model. Common justifications and potential issues with this approach are explored with recommendations made for future clinical and research practice.

A policy-into-practice intervention to increase the uptake of evidence-based management of low back pain in primary care: a prospective cohort study

Background

Persistent non-specific low back pain (nsLBP) is poorly understood by the general community, by educators, researchers and health professionals, making effective care problematic. This study evaluated the effectiveness of a policy-into-practice intervention developed for primary care physicians (PCPs).

Methods

To encourage PCPs to adopt practical evidence-based approaches and facilitate time-efficient, integrated management of patients with nsLBP, we developed an interdisciplinary evidence-based, practical pain education program (gPEP) based on a contemporary biopsychosocial framework. One hundred and twenty six PCPs from primary care settings in Western Australia were recruited. PCPs participated in a 6.5-hour gPEP. Self-report measures recorded at baseline and at 2 months post-intervention included PCPs' attitudes, beliefs (modified Health Care Providers Pain and Impairment Relationship Scale (HC-PAIRS), evidence-based clinical practices (knowledge and skills regarding nsLBP management: 5-point Likert scale with 1 =  nil and 5 =  excellent) and practice behaviours (recommendations based on a patient vignette; 5-point Likert scale).

Results

Ninety one PCPs participated (attendance rate of 72%; post-intervention response rate 88%). PCP-responders adopted more positive, guideline-consistent beliefs, evidenced by clinically significant HC-PAIRS score differences (mean change  = −5.6±8.2, p<0.0001; 95% confidence interval: −7.6 to −3.6) and significant positive shifts on all measures of clinical knowledge and skills (p<0.0001 for all questions). Self management strategies were recommended more frequently post-intervention. The majority of responders who were guideline-inconsistent for work and bed rest recommendations (82% and 62% respectively) at pre-intervention, gave guideline-consistent responses at post-intervention.

Conclusion

An interprofessional pain education program set within a framework that aligns health policy and practice, encourages PCPs to adopt more self-reported evidence-based attitudes, beliefs and clinical behaviours in their management of patients with nsLBP. However, further research is required to determine cost effectiveness of this approach when compared with other modes of educational delivery and to examine PCP behaviours in actual clinical practice.

Non-specific low back pain

Non-specific low back pain has become a major public health problem worldwide. The lifetime prevalence of low back pain is reported to be as high as 84%, and the prevalence of chronic low back pain is about 23%, with 11-12% of the population being disabled by low back pain. Mechanical factors, such as lifting and carrying, probably do not have a major pathogenic role, but genetic constitution is important. History taking and clinical examination are included in most diagnostic guidelines, but the use of clinical imaging for diagnosis should be restricted. The mechanism of action of many treatments is unclear, and effect sizes of most treatments are low. Both patient preferences and clinical evidence should be taken into account for pain management, but generally self-management, with appropriate support, is recommended and surgery and overtreatment should be avoided.

Barriers and progress in the treatment of low back pain

Low back pain is a common and costly condition and for most people is likely to be a recurrent problem throughout their lifetime. The management of patients with low back pain has been positively influenced by the rise in high quality clinical trials and systematic reviews in recent decades, and this body of evidence, synthesized in many clinical practice guidelines, has improved our knowledge about which treatments for low back pain are useful and which are not. For the largest group of patients, those with non-specific low back pain for whom a clear diagnosis cannot be given, the reality is that the treatments we have to offer tend to produce small effects, often only in the short term and none appear to effectively change long-term prognosis. This commentary summarizes the array of treatments currently available, notes the results of recent trials and guidelines and considers alternative approaches that may prove more valuable in achieving better patient outcomes in the future.

Lumbar disc degeneration and genetic factors are the main risk factors for low back pain in women: the UK Twin Spine Study

Objective

Low back pain (LBP) is a common musculoskeletal disorder, but it is still unclear which individuals develop it. The authors examined the contribution of genetic factors, lumbar disc degeneration (LDD) and other risk factors in a female sample of the general population.

Material and Methods

A cross-sectional study was conducted among 2256 women (371 and 698 monozygotic and dizygotic twin pairs and 29 sibling pairs and 60 singletons) with a mean age of 50 years (18–84). A self-reported validated questionnaire was used to collect back pain data. Risk factors including body weight, smoking, occupation, physical exercise and MRI assessed LDD were measured. Data analysis included logistic regression and variance decomposition.

Results

The major factors associated with LBP included genetic background, with OR approximately 6 if the monozygotic co-twin had LBP, or 2.2 if she was a dizygotic co-twin. In addition, LDD and overweight were highly significantly (p<0.001) associated with non-specific LBP. The single most important risk factor was the amount of LDD. After adjustment for other risk factors, the individuals who exhibited advanced LDD (90% vs 10%) had 3.2 higher odds of manifesting LBP. The data also showed a significant (p<0.001) genetic correlation between the LBP and LDD measurements, suggesting that approximately 11–13% of the genetic effects are shared by LDD and LBP.

Conclusions

The main risk factors for reported episodes of severe and disabling LBP in UK women include the degree of LDD as assessed by MRI, being overweight and genetic heritability.