Prognosis of Patients With Neuropathic Low Back-Related Leg Pain: An Exploratory Study Using Prospective Data From UK Primary Care.

This prospective cohort study investigates the prognosis of patients with neuropathic low back-related leg pain consulting in UK primary care. Data from 511 patients were collected using standardised baseline clinical examinations (including magnetic resonance imaging scan findings), self-report questionnaires at baseline, 4 months, 12 months, and 3 years. Cases of possible neuropathic pain (NP) and persistent-NP were identified using either of 2 definitions: 1) clinical diagnosis of sciatica, 2) self-report version of leeds assessment for neurological symptoms and signs (s-LANSS). Mixed-effects models compared pain intensity (highest of mean leg or mean back pain [0-10 Numerical Rating Scale]) over 3-years between persistent-NP versus non-persistent-NP based on 1) clinical diagnosis, 2) s-LANSS. Logistic regression examined associations between potential prognostic factors and persistent-NP at 4 months based on the 2 NP definitions. At 4-months, using both definitions: 1) approximately 4 out of 10 patients had persistent-NP, 2) mean pain intensity was higher for patients with persistent-NP at all follow-up points compared to those without, 3) only pain self-efficacy was significantly associated with persistent-NP (s-LANSS: OR .98, sciatica: .98), but it did not predict cases of persistent-NP in either multivariable model. Based on factors routinely collected from self-report and clinical examination, it was not possible to predict persistent-NP in this population. PERSPECTIVE: This study provides evidence that neuropathic back-related leg pain in patients consulting in primary care is not always persistent. Patients with persistent neuropathic pain had worse outcomes than those without. Neither leg pain intensity, pain self-efficacy nor MRI scan findings predicted cases of persistent neuropathic pain in this patient population.

Predictors of outcome in sciatica patients following an epidural steroid injection: the POiSE prospective observational cohort study protocol.

INTRODUCTION: Sciatica can be very painful and, in most cases, is due to pressure on a spinal nerve root from a disc herniation with associated inflammation. For some patients, the pain persists, and one management option is a spinal epidural steroid injection (ESI). The aim of an ESI is to relieve leg pain, improve function and reduce the need for surgery. ESIs work well in some patients but not in others, but we cannot identify these patient subgroups currently. This study aims to identify factors, including patient characteristics, clinical examination and imaging findings, that help in predicting who does well and who does not after an ESI. The overall objective is to develop a prognostic model to support individualised patient and clinical decision-making regarding ESI. METHODS: POiSE is a prospective cohort study of 439 patients with sciatica referred by their clinician for an ESI. Participants will receive weekly text messages until 12 weeks following their ESIand then again at 24 weeks following their ESI to collect data on leg pain severity. Questionnaires will be sent to participants at baseline, 6, 12 and 24 weeks after their ESI to collect data on pain, disability, recovery and additional interventions. The prognosis for the cohort will be described. The primary outcome measure for the prognostic model is leg pain at 6 weeks. Prognostic models will also be developed for secondary outcomes of disability and recovery at 6 weeks and additional interventions at 24 weeks following ESI. Statistical analyses will include multivariable linear and logistic regression with mixed effects model. ETHICS AND DISSEMINATION: The POiSE study has received ethical approval (South Central Berkshire B Research Ethics Committee 21/SC/0257). Dissemination will be guided by our patient and public engagement group and will include scientific publications, conference presentations and social media.

Recommendations for terminology and the identification of neuropathic pain in people with spine-related leg pain. Outcomes from the NeuPSIG working group.

ABSTRACT: Pain radiating from the spine into the leg is commonly referred to as "sciatica," "Sciatica" may include various conditions such as radicular pain or painful radiculopathy. It may be associated with significant consequences for the person living with the condition, imposing a reduced quality of life and substantial direct and indirect costs. The main challenges associated with a diagnosis of "sciatica" include those related to the inconsistent use of terminology for the diagnostic labels and the identification of neuropathic pain. These challenges hinder collective clinical and scientific understanding regarding these conditions. In this position paper, we describe the outcome of a working group commissioned by the Neuropathic Pain Special Interest Group (NeuPSIG) of the International Association for the Study of Pain (IASP) which was tasked with the following objectives: (1) to revise the use of terminology for classifying spine-related leg pain and (2) to propose a way forward on the identification of neuropathic pain in the context of spine-related leg pain. The panel recommended discouraging the term "sciatica" for use in clinical practice and research without further specification of what it entails. The term "spine-related leg pain" is proposed as an umbrella term to include the case definitions of somatic referred pain and radicular pain with and without radiculopathy. The panel proposed an adaptation of the neuropathic pain grading system in the context of spine-related leg pain to facilitate the identification of neuropathic pain and initiation of specific management in this patient population.

Prognostic factors associated with outcome following an epidural steroid injection for disc-related sciatica: a systematic review and narrative synthesis.

PURPOSE: Clinical guidelines recommend epidural steroid injection (ESI) as a treatment option for severe disc-related sciatica, but there is considerable uncertainty about its effectiveness. Currently, we know very little about factors that might be associated with good or poor outcomes from ESI. The aim of this systematic review was to synthesise and appraise the evidence investigating prognostic factors associated with outcomes following ESI for patients with imaging confirmed disc-related sciatica. METHODS: The search strategy involved the electronic databases Medline, Embase, CINAHL Plus, PsycINFO and reference lists of eligible studies. Selected papers were quality appraised independently by two reviewers using the Quality in Prognosis Studies tool. Between-study heterogeneity precluded statistical pooling of results. RESULTS: 3094 citations were identified; 15 studies were eligible. Overall study quality was low with all judged to have moderate or high risk of bias. Forty-two prognostic factors were identified but were measured inconsistently. The most commonly assessed prognostic factors were related to pain and function (n = 10 studies), imaging features (n = 8 studies), patient socio-demographics (n = 7 studies), health and lifestyle (n = 6 studies), clinical assessment findings (n = 4 studies) and injection level (n = 4 studies). No prognostic factor was found to be consistently associated with outcomes following ESI. Most studies found no association or results that conflicted with other studies. CONCLUSIONS: There is little, and low quality, evidence to guide practice in terms of factors that predict outcomes in patients following ESI for disc-related sciatica. The results can help inform some of the decisions about potential prognostic factors that should be assessed in future well-designed prospective cohort studies.

The STarT Back stratified care model for nonspecific low back pain: a model-based evaluation of long-term cost-effectiveness.

ABSTRACT: The STarT Back approach comprises subgrouping patients with low back pain (LBP) according to the risk of persistent LBP-related disability, with appropriate matched treatments. In a 12-month clinical trial and implementation study, this stratified care approach was clinically and cost-effective compared with usual, nonstratified care. Despite the chronic nature of LBP and associated economic burden, model-based economic evaluations in LBP are rare and have shortcomings. This study therefore produces a de novo decision model of this stratified care approach for LBP management to estimate the long-term cost-effectiveness and address methodological concerns in LBP modelling. A cost-utility analysis from the National Health Service perspective compared stratified care with usual care in patients consulting in primary care with nonspecific LBP. A Markov state-transition model was constructed where patient prognosis over 10 years was dependent on physical function achieved at 12 months. Data from the clinical trial and implementation study provided short-term model parameters, with extrapolation using 2 cohort studies of usual care in LBP. Base-case results indicate this model of stratified care is cost-effective, delivering 0.14 additional quality-adjusted life years at a cost saving of £135.19 per patient over a time horizon of 10 years. Sensitivity analyses indicate the approach is likely to be cost-effective in all scenarios and cost saving in most. It is likely this stratified care model will help reduce unnecessary healthcare usage while improving the patient's quality of life. Although decision-analytic modelling is used in many conditions, its use has been underexplored in LBP, and this study also addresses associated methodological challenges.

Stratified versus usual care for the management of primary care patients with sciatica: the SCOPiC RCT.

BACKGROUND: Sciatica has a substantial impact on patients and society. Current care is 'stepped', comprising an initial period of simple measures of advice and analgesia, for most patients, commonly followed by physiotherapy, and then by more intensive interventions if symptoms fail to resolve. No study has yet tested a model of stratified care in which patients are subgrouped and matched to different care pathways based on their prognosis and clinical characteristics. OBJECTIVES: The objectives were to investigate the clinical effectiveness and cost-effectiveness of a stratified care model compared with usual, non-stratified care. DESIGN: This was a two-parallel group, multicentre, pragmatic, 1 : 1 randomised controlled trial. SETTING: Participants were recruited from primary care (42 general practices) in North Staffordshire, North Shropshire/Wales and Cheshire in the UK. PARTICIPANTS: Eligible patients were aged ≥ 18 years, had suspected sciatica, had access to a mobile phone/landline, were not pregnant, were not receiving treatment for the same problem and had not had previous spinal surgery. INTERVENTIONS: In stratified care, a combination of prognostic and clinical criteria associated with referral to spinal specialist services was used to allocate patients to one of three groups for matched care pathways. Group 1 received advice and up to two sessions of physiotherapy, group 2 received up to six sessions of physiotherapy, and group 3 was fast-tracked to magnetic resonance imaging and spinal specialist opinion. Usual care was based on the stepped-care approach without the use of any stratification tools/algorithms. Patients were randomised using a remote web-based randomisation service. MAIN OUTCOME MEASURES: The primary outcome was time to first resolution of sciatica symptoms (six point ordinal scale, collected via text messages). Secondary outcomes (at 4 and 12 months) included pain, function, psychological health, days lost from work, work productivity, satisfaction with care and health-care use. A cost-utility analysis was undertaken over 12 months. A qualitative study explored patients' and clinicians' views of the fast-track care pathway to a spinal specialist. RESULTS: A total of 476 patients were randomised (238 in each arm). For the primary outcome, the overall response rate was 89.3% (88.3% and 90.3% in the stratified and usual care arms, respectively). Relief from symptoms was slightly faster (2 weeks median difference) in the stratified care arm, but this difference was not statistically significant (hazard ratio 1.14, 95% confidence interval 0.89 to 1.46; p = 0.288). On average, participants in both arms reported good improvement from baseline, on most outcomes, over time. Following the assessment at the research clinic, most participants in the usual care arm were referred to physiotherapy. CONCLUSIONS: The stratified care model tested in this trial was not more clinically effective than usual care, and was not likely to be a cost-effective option. The fast-track pathway was felt to be acceptable to both patients and clinicians; however, clinicians expressed reluctance to consider invasive procedures if symptoms were of short duration. LIMITATIONS: Participants in the usual care arm, on average, reported good outcomes, making it challenging to demonstrate superiority of stratified care. The performance of the algorithm used to allocate patients to treatment pathways may have influenced results. FUTURE WORK: Other approaches to stratified care may provide superior outcomes for sciatica. TRIAL REGISTRATION: Current Controlled Trials ISRCTN75449581. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 49. See the NIHR Journals Library website for further project information.

Sciatica is pain that spreads into the leg because of a trapped nerve in the lower back. It can be a very painful condition that affects everyday life and ability to work. People with sciatica usually see their general practitioner first; if they do not get better over time, they may be referred to a physiotherapist or, eventually, to a spinal specialist. It is difficult to know which sciatica patient will do well without much treatment and who might need to see a physiotherapist or spinal specialist sooner. Stratified care is an approach aiming to help decide, early on, which patients need to see which health professionals. It has previously been shown to be helpful for patients with lower-back pain. In a trial of 476 patients with sciatica a stratified care model was tested to see if it led to faster improvements in sciatica-related leg pain, when compared with usual care. Adults seeing their general practitioner with sciatica were invited to attend a research clinic. Those willing to take part were randomly assigned to stratified care or usual care. Patients in the stratified care arm were referred either to physiotherapy for a short or a longer course of treatment, or to undergo magnetic resonance imaging and see a spinal specialist with the magnetic resonance imaging results within 4 weeks. Pain, function and quality-of-life data were collected over 12 months using text messages and questionnaires. Although patients in the stratified care arm improved slightly more quickly (2 weeks, on average), we did not find convincing evidence that stratified care led to better results than usual care. On average, most patients in both trial arms improved in a similar way over 12 months. The stratified care model tested in this trial did not lead to faster recovery for patients with sciatica than usual care.

Prevalence, Characteristics, and Clinical Course of Neuropathic Pain in Primary Care Patients Consulting With Low Back-related Leg Pain.

OBJECTIVES: Little is known about the epidemiology of neuropathic pain in primary care patients consulting with low back-related leg pain. We aimed to describe prevalence, characteristics, and clinical course of low back-related leg pain patients with and without neuropathic pain, consulting with their family doctor in the United Kingdom. MATERIALS AND METHODS: This was a prospective cohort study. Data were collected using a standardized baseline clinical examination and self-report questionnaires at baseline, 4, 12, and 36 months. We identified cases of neuropathic pain using 3 definitions: 2 based on clinical diagnosis (sciatica, with and without evidence of nerve root compression on magnetic resonance imaging), one on the self-report version of Leeds Assessment for Neurological Symptoms and Signs. Differences between patients with and without neuropathic pain were analyzed comparing each definition. Clinical course (mean pain intensity measured as the highest of leg or back pain intensity: mean of 3 Numerical Rating Scales, each 0 to 10) was investigated using linear mixed models over 36 months. RESULTS: Prevalence of neuropathic pain varied from 48% to 74% according to definition used. At baseline, patients with neuropathic pain had more severe leg pain intensity, lower pain self-efficacy, more patients had sensory loss than those without. Distinct profiles were apparent depending on neuropathic pain definition. Mean pain intensity reduced after 4 months (6.1 to 3.9 [sciatica]), most rapidly in cases defined by clinical diagnosis. DISCUSSION: This research provides new information on the clinical course of neuropathic pain and a better understanding of neuropathic pain in low back-related leg pain patients consulting in primary care.

Stratified care versus usual care for management of patients presenting with sciatica in primary care (SCOPiC): a randomised controlled trial.

BACKGROUND: Sciatica has a substantial impact on individuals and society. Stratified care has been shown to lead to better outcomes among patients with non-specific low back pain, but it has not been tested for sciatica. We aimed to investigate the clinical and cost-effectiveness of stratified care versus non-stratified usual care for patients presenting with sciatica in primary care. METHODS: We did a two-parallel arm, pragmatic, randomised controlled trial across three centres in the UK (North Staffordshire, North Shropshire/Wales, and Cheshire). Eligible patients were aged 18 years or older, had a clinical diagnosis of sciatica, access to a mobile phone or landline number, were not pregnant, were not currently receiving treatment for the same problem, and had no previous spinal surgery. Patients were recruited from general practices and randomly assigned (1:1) by a remote web-based service to stratified care or usual care, stratified by centre and stratification group allocation. In the stratified care arm, a combination of prognostic and clinical criteria associated with referral to spinal specialist services were used to allocate patients to one of three groups for matched care pathways. Group 1 was offered brief advice and support in up to two physiotherapy sessions; group 2 was offered up to six physiotherapy sessions; and group 3 was fast-tracked to MRI and spinal specialist assessment within 4 weeks of randomisation. The primary outcome was self-reported time to first resolution of sciatica symptoms, defined as "completely recovered" or "much better" on a 6-point ordinal scale, collected via text messages or telephone calls. Analyses were by intention to treat. Health-care costs and cost-effectiveness were also assessed. This trial is registered on the ISRCTN registry, ISRCTN75449581. FINDINGS: Between May 28, 2015, and July 18, 2017, 476 patients from 42 general practices around three UK centres were randomly assigned to stratified care or usual care (238 in each arm). For the primary outcome, the overall response rate was 89% (9467 of 10 601 text messages sent; 4688 [88%] of 5310 in the stratified care arm and 4779 [90%] of 5291 in the usual care arm). Median time to symptom resolution was 10 weeks (95% CI 6·4-13·6) in the stratified care arm and 12 weeks (9·4-14·6) in the usual care arm, with the survival analysis showing no significant difference between the arms (hazard ratio 1·14 [95% CI 0·89-1·46]). Stratified care was not cost-effective compared to usual care. INTERPRETATION: The stratified care model for patients with sciatica consulting in primary care was not better than usual care for either clinical or health economic outcomes. These results do not support a transition to this stratified care model for patients with sciatica. FUNDING: National Institute for Health Research.

Patients' and clinicians' perspectives on a 'fast-track' pathway for patients with sciatica in primary care: qualitative findings from the SCOPiC stratified care trial.

BACKGROUND: Sciatica is common and associated with significant impacts for the individual and society. The SCOPiC randomised controlled trial (RCT) (trial registration: ISRCTN75449581 ) tested stratified primary care for sciatica by subgrouping patients into one of three groups based on prognostic and clinical indicators. Patients in one group were 'fast-tracked' for a magnetic resonance imaging (MRI) scan and spinal specialist opinion. This paper reports qualitative research exploring patients' and clinicians' perspectives on the acceptability of this 'fast-track' pathway. METHODS: Semi-structured interviews were conducted with 20 patients and 20 clinicians (general practitioners, spinal specialist physiotherapists, spinal surgeons). Data were analysed thematically and findings explored using Normalisation Process Theory (NPT) and 'boundary objects' concept. RESULTS: Whilst the 'fast-track' pathway achieved a degree of 'coherence' (i.e. made sense) to both patients and clinicians, particularly in relation to providing early reassurance based on MRI scan findings, it was less 'meaningful' to some clinicians for managing patients with acute symptoms, reflecting a reluctance to move away from the usual 'stepped care' approach. Both groups felt a key limitation of the pathway was that it did not shorten patient waiting times between their spinal specialist consultation and further treatments. CONCLUSION: Findings contribute new knowledge about patients' and clinicians' perspectives on the role of imaging and spinal specialist opinion in the management of sciatica, and provide important insights for understanding the 'fast-track' pathway, as part of the stratified care model tested in the RCT. Future research into the early referral of patients with sciatica for investigation and specialist opinion should include strategies to support clinician behaviour change; as well as take into account the role of imaging in providing reassurance to patients with severe symptoms in cases where imaging reveals a clear explanation for the patient's pain, and where this is accompanied by a thorough explanation from a trusted clinical expert.

New insight to the characteristics and clinical course of clusters of patients with imaging confirmed disc-related sciatica.

BACKGROUND: Referral to secondary care is common for a considerable proportion of patients with persistent sciatica symptoms. It is unclear if information from clinical assessment can further identify distinct subgroups of disc-related sciatica, with perhaps different clinical courses. AIMS: This study aims to identify and describe clusters of imaging confirmed disc-related sciatica patients using latent class analysis, and compare their clinical course. METHODS: The study population were 466 patients with disc-related sciatica. Variables from clinical assessment were included in the analysis. Characteristics of the identified clusters were described and their clinical course over 2 years was compared. RESULTS: A four-cluster solution was optimal. Cluster 1 (n = 110) had mild back and leg pain; cluster 2 (n = 59) had moderate back and leg pain; cluster 3 (n = 158) had mild back pain and severe leg pain; cluster 4 (n = 139) had severe back and leg pain. Patients in cluster 4 had the most severe profile in terms of disability, distress and comorbidity and the lowest reported global change and the smallest proportion of patients with a successful outcome at 2 years. Of the 135 patients who underwent surgery, 42% and 41% were in clusters 3 and 4, respectively. CONCLUSIONS: Using a strict diagnosis of sciatica, this work identified four clusters of patients primarily differentiated by back and leg pain severity. Patients with severe back and leg pain had the most severe profile at baseline and follow-up irrespective of intervention. This simple classification system may be useful when considering prognosis and management with sciatica patients. SIGNIFICANCE: Using data from a large observational prospective study, this work identifies four distinct clusters of patients with imaging confirmed disc-related sciatica. This classification could be used when considering prognosis and management with sciatica patients at their initial consultation.

Subgrouping patients with sciatica in primary care for matched care pathways: development of a subgrouping algorithm.

BACKGROUND: Sciatica is a painful condition managed by a stepped care approach for most patients. Currently, there are no decision-making tools to guide matching care pathways for patients with sciatica without evidence of serious pathology, early in their presentation. This study sought to develop an algorithm to subgroup primary care patients with sciatica, for initial decision-making for matched care pathways, including fast-track referral to investigations and specialist spinal opinion. METHODS: This was an analysis of existing data from a UK NHS cohort study of patients consulting in primary care with sciatica (n = 429). Factors potentially associated with referral to specialist services, were identified from the literature and clinical opinion. Percentage of patients fast-tracked to specialists, sensitivity, specificity, positive and negative predictive values for identifying this subgroup, were calculated. RESULTS: The algorithm allocates patients to 1 of 3 groups, combining information about four clinical characteristics, and risk of poor prognosis (low, medium or high risk) in terms of pain-related persistent disability. Patients at low risk of poor prognosis, irrespective of clinical characteristics, are allocated to group 1. Patients at medium risk of poor prognosis who have all four clinical characteristics, and patients at high risk of poor prognosis with any three of the clinical characteristics, are allocated to group 3. The remainder are allocated to group 2. Sensitivity, specificity and positive predictive value of the algorithm for patient allocation to fast-track group 3, were 51, 73 and 22% respectively. CONCLUSION: We developed an algorithm to support clinical decisions regarding early referral for primary care patients with sciatica. Limitations of this study include the low positive predictive value and use of data from one cohort only. On-going research is investigating whether the use of this algorithm and the linked care pathways, leads to faster resolution of sciatica symptoms.

Factors associated with costs and health outcomes in patients with Back and leg pain in primary care: a prospective cohort analysis.

BACKGROUND: There is limited research on the economic burden of low back-related leg pain, including sciatica. The aim of this study was to describe healthcare resource utilisation and factors associated with cost and health outcomes in primary care patients consulting with symptoms of low back-related leg pain including sciatica. METHODS: This study is a prospective cohort of 609 adults visiting their family doctor with low back-related leg pain, with or without sciatica in a United Kingdom (UK) Setting. Participants completed questionnaires, underwent clinical assessments, received an MRI scan, and were followed-up for 12-months. The economic analysis outcome was the quality-adjusted life year (QALY) calculated from the EQ-5D-3 L data obtained at baseline, 4 and 12-months. Costs were measured based on patient self-reported information on resource use due to back-related leg pain and results are presented from a UK National Health Service (NHS) and Societal perspective. Factors associated with costs and outcomes were obtained using a generalised linear model. RESULTS: Base-case results showed improved health outcomes over 12-months for the whole cohort and slightly higher QALYs for patients in the sciatica group. NHS resource use was highest for physiotherapy and GP visits, and work-related productivity loss highest from a societal perspective. The sciatica group was associated with significantly higher work-related productivity costs. Cost was significantly associated with factors such as self-rated general health and care received as part of the study, while quality of life was significantly predicted by self-rated general health, and pain intensity, depression, and disability scores. CONCLUSIONS: Our results contribute to understanding the economics of low back- related leg pain and sciatica and may provide guidance for future actions on cost reduction and health care improvement strategies. TRIAL REGISTRATION: 13/09/2011 Retrospectively registered; ISRCTN62880786 .

Inflammatory biomarkers do not distinguish between patients with sciatica and referred leg pain within a primary care population: results from a nested study within the ATLAS cohort.

BACKGROUND: There is increasing interest in the role of pro-inflammatory cytokines in the pathogenesis of sciatica and whether these could be potential targets for treatment. We sought to investigate serum biomarker levels in patients with low back-related leg pain, including sciatica. METHODS: Primary care consulters aged > 18 with low back-related leg pain were recruited to a cohort study (ATLAS). Participants underwent a standardised clinical assessment, lumbar spine MRI and a subsample (n = 119) had samples taken for biomarker analysis. Participants were classified having: a) clinically confirmed sciatica or referred leg pain, and then subdivided into those with (or without) MRI confirmed nerve root compression due to disc prolapse. Seventeen key cytokines, chemokines and matrix metalloproteinases (MMPs) implicated in sciatica pathogenesis including TNFα and IL-6, were assayed in duplicate using commercial multiplex detection kits and measured using a Luminex suspension array system. Median biomarker levels were compared between the groups using a Mann Whitney U test. Multivariate logistic regression analysis was used to investigate the association between clinical measures and biomarker levels adjusted for possible confounders such as age, sex, and symptom duration. RESULTS: No difference was found in the serum level of any of the 17 biomarkers tested in patients with (n = 93) or without (n = 26) clinically confirmed sciatica, nor between those with (n = 44) or without (n = 49) sciatica and MRI confirmed nerve root compression. CONCLUSION: In this cohort, no significant differences in serum levels of TNFα, IL-6 or any other biomarkers were seen between patients with sciatica and those with back pain with referred leg pain. These results suggest that in patients with low back-related leg pain, serum markers associated with inflammation do not discriminate between patients with or without clinically confirmed sciatica or between those with or without evidence of nerve root compression on MRI.

Systematic Review of Decision Analytic Modelling in Economic Evaluations of Low Back Pain and Sciatica.

BACKGROUND: Low back pain (LBP) and sciatica place significant burden on individuals and healthcare systems, with societal costs alone likely to be in excess of £15 billion. Two recent systematic reviews for LBP and sciatica identified a shortage of modelling studies in both conditions. OBJECTIVES: The aim of this systematic review was to document existing model-based economic evaluations for the treatment and management of both conditions; critically appraise current modelling techniques, analytical methods, data inputs, and structure, using narrative synthesis; and identify unresolved methodological problems and gaps in the literature. METHODS: A systematic literature review was conducted whereby 6512 records were extracted from 11 databases, with no date limits imposed. Studies were abstracted according to a predesigned protocol, whereby they must be economic evaluations that employed an economic decision model and considered any management approach for LBP and sciatica. Study abstraction was initially performed by one reviewer who removed duplicates and screened titles to remove irrelevant studies. Overall, 133 potential studies for inclusion were then screened independently by other reviewers. Consensus was reached between reviewers regarding final inclusion. RESULTS: Twenty-one publications of 20 unique models were included in the review, five of which were modelling studies in LBP and 16 in sciatica. Results revealed a poor standard of modelling in both conditions, particularly regarding modelling techniques, analytical methods, and data quality. Specific issues relate to inappropriate representation of both conditions in terms of health states, insufficient time horizons, and use of inappropriate utility values. CONCLUSION: High-quality modelling studies, which reflect modelling best practice, as well as contemporary clinical understandings of both conditions, are required to enhance the economic evidence for treatments for both conditions.

Biographical suspension and liminality of Self in accounts of severe sciatica.

Sciatica is a common form of low back pain (LBP) that has been identified as distinct both in terms of the persistence and severity of symptoms. Little research has explored individual experiences of sciatica, and none focuses on individuals with the most severe, long-lasting symptoms who may experience the most profound impact. This paper addresses this gap through proposing a theoretical framework for understanding such experiences, that of biographical suspension as a form of liminality of Self. Twenty semi-structured interviews were conducted with individuals with severe sciatic symptoms between January 2016‒March 2017, as part of the UK-based SCOPiC (SCiatica Outcomes in Primary Care) randomised controlled trial. Data were analysed thematically using the constant comparison method. The concept of 'biographical suspension', originally developed in LBP, emerged as one whereby individuals put life on-hold in the expectation of an eventual return to their former, pain-free selves. Deeper analysis extended this concept to a form of liminality, whereby individuals are caught between pre- and post-sickness selves, unable to fully identify with either. This liminality is underpinned by ongoing beliefs about sciatica as a temporary and fixable 'injury' rather than long-term 'illness', even among those with long-lasting symptoms. This led to a disjuncture between individuals' ongoing pain beliefs and experiences, resulting in longer-term psychological impacts. Biographical suspension is further conceptualised as an experiential stage giving rise to four distinct short-term trajectories: i) symptom resolution leading individuals to occupy a clearly post-liminal state; ii) remaining in suspended liminality; iii) ongoing symptoms leading to a post-liminal state of resignation; ix) a state of being both between sickness and wellness, and straddling hope and fear; thus exemplifying differing states of liminality experienced over time. Findings have implications for the support provided in clinical settings to individuals who may struggle to self-manage due to sustained liminality of Self.

Factors associated with physiotherapists' preference for MRI in primary care patients with low back and leg pain.

BACKGROUND: Criticisms about overuse of MRI in low back pain are well documented. Yet, with the exception of suspicion of serious pathology, little is known about factors that influence clinicians' preference for magnetic resonance imaging (MRI) at first consultation. OBJECTIVE: To explore factors associated with physiotherapists' preference for MRI for patients consulting with benign low back and leg pain (LBLP) including sciatica. DESIGN: Cross-sectional cohort study. METHODS: Data were collected from 607 primary care LBLP patients participating in the ATLAS cohort study. Following clinical assessment, physiotherapists documented whether he/she wanted the patient to have an MRI. Factors potentially associated with physiotherapists' preference for imaging were selected a priori from patient characteristics and clinical assessment findings. A mixed-effects logistic regression model examined the associations between these factors and physiotherapists' preference for MRI. RESULTS: Physiotherapists expressed a preference for MRI in 32% (196/607) of patients, of whom 22 did not have a clinical diagnosis of sciatica (radiculopathy). Factors associated with preference for MRI included; clinical diagnosis of sciatica (OR 4.23: 95% CI 2.29, 7.81), greater than 3 months pain duration (2.61: 1.58, 4.30), high pain intensity (1.24: 1.11, 1.37), patient's low expectation of improvement (2.40: 1.50, 3.83), physiotherapist's confidence in their diagnosis (1.19: 1.07, 1.33), with greater confidence associated with higher probability for MRI preference. CONCLUSION: A clinical diagnosis of sciatica and longer symptom duration were most strongly associated with physiotherapists' preference for MRI. Given current best practice guidelines, these appear to be justifiable reasons for MRI preference at first consultation.

Lessons learnt from a discontinued randomised controlled trial: adalimumab injection compared with placebo for patients receiving physiotherapy treatment for sciatica (Subcutaneous Injection of Adalimumab Trial compared with Control: SCIATiC).

BACKGROUND: Adalimumab, a biological treatment targeting tumour necrosis factor α, might be useful in sciatica. This paper describes the challenges faced when developing a new treatment pathway for a randomised controlled trial of adalimumab for people with sciatica, as well as the reasons why the trial discussed was stopped early. METHODS: A pragmatic, parallel group, randomised controlled trial with blinded (masked) participants, clinicians, outcome assessment and statistical analysis was conducted in six UK sites. Participants were identified and recruited from general practices, musculoskeletal services and outpatient physiotherapy clinics. They were adults with persistent symptoms of sciatica of 1 to 6 months' duration with moderate to high level of disability. Eligibility was assessed by research physiotherapists according to clinical criteria, and participants were randomised to receive two doses of adalimumab (80 mg then 40 mg 2 weeks later) or saline placebo subcutaneous injections in the posterior lateral thigh. Both groups were referred for a course of physiotherapy. Outcomes were measured at baseline, 6-week, 6-month and 12-month follow-up. The main outcome measure was disability measured using the Oswestry Disability Index. The planned sample size was 332, with the first 50 in an internal pilot phase. RESULTS: The internal pilot phase was discontinued after 10 months from opening owing to low recruitment (two of the six sites active, eight participants recruited). There were several challenges: contractual delays; one site did not complete contract negotiations, and two sites signed contracts shortly before trial closure; site withdrawal owing to patient safety concerns; difficulties obtaining excess treatment costs; and in the two sites that did recruit, recruitment was slower than planned because of operational issues and low uptake by potential participants. CONCLUSIONS: Improved patient care requires robust clinical research within contexts in which treatments can realistically be provided. Step changes in treatment, such as the introduction of biologic treatments for severe sciatica, raise complex issues that can delay trial initiation and retard recruitment. Additional preparatory work might be required before testing novel treatments. A randomised controlled trial of tumour necrosis factor-α blockade is still needed to determine its cost-effectiveness in severe sciatica. TRIAL REGISTRATION: Current Controlled Trials, ISRCTN14569274 . Registered on 15 December 2014.

Clinical diagnostic model for sciatica developed in primary care patients with low back-related leg pain.

BACKGROUND: Identification of sciatica may assist timely management but can be challenging in clinical practice. Diagnostic models to identify sciatica have mainly been developed in secondary care settings with conflicting reference standard selection. This study explores the challenges of reference standard selection and aims to ascertain which combination of clinical assessment items best identify sciatica in people seeking primary healthcare. METHODS: Data on 394 low back-related leg pain consulters were analysed. Potential sciatica indicators were seven clinical assessment items. Two reference standards were used: (i) high confidence sciatica clinical diagnosis; (ii) high confidence sciatica clinical diagnosis with confirmatory magnetic resonance imaging findings. Multivariable logistic regression models were produced for both reference standards. A tool predicting sciatica diagnosis in low back-related leg pain was derived. Latent class modelling explored the validity of the reference standard. RESULTS: Model (i) retained five items; model (ii) retained six items. Four items remained in both models: below knee pain, leg pain worse than back pain, positive neural tension tests and neurological deficit. Model (i) was well calibrated (p = 0.18), discrimination was area under the receiver operating characteristic curve (AUC) 0.95 (95% CI 0.93, 0.98). Model (ii) showed good discrimination (AUC 0.82; 0.78, 0.86) but poor calibration (p = 0.004). Bootstrapping revealed minimal overfitting in both models. Agreement between the two latent classes and clinical diagnosis groups defined by model (i) was substantial, and fair for model (ii). CONCLUSION: Four clinical assessment items were common in both reference standard definitions of sciatica. A simple scoring tool for identifying sciatica was developed. These criteria could be used clinically and in research to improve accuracy of identification of this subgroup of back pain patients.

Determining One-Year Trajectories of Low-Back-Related Leg Pain in Primary Care Patients: Growth Mixture Modeling of a Prospective Cohort Study.

OBJECTIVE: The clinical presentation and outcome of patients with back and leg pain in primary care are heterogeneous and may be better understood by identification of homogeneous and clinically meaningful subgroups. Subgroups of patients with different back pain trajectories have been identified, but little is known about the trajectories for patients with back-related leg pain. This study sought to identify distinct leg pain trajectories, and baseline characteristics associated with membership of each group, in primary care patients. METHODS: Monthly data on leg pain intensity were collected over 12 months for 609 patients participating in a prospective cohort study of adult patients seeking health care for low-back and leg pain, including sciatica, of any duration and severity, from their general practitioner. Growth mixture modeling was used to identify clusters of patients with distinct leg pain trajectories. Trajectories were characterized using baseline demographic and clinical examination data. Multinomial logistic regression was used to predict latent class membership, with a range of covariates. RESULTS: Four patient clusters were identified: improving mild pain (58%), persistent moderate pain (26%), persistent severe pain (13%), and improving severe pain (3%). Clusters showed statistically significant differences in a number of baseline characteristics. CONCLUSION: Four trajectories of leg pain were identified. Clusters 1, 2, and 3 were generally comparable to back pain trajectories, while cluster 4, with major improvement in pain, is infrequently identified. Awareness of such distinct patient groups improves understanding of the course of leg pain and may provide a basis of classification for intervention.

Novel approach to characterising individuals with low back-related leg pain: cluster identification with latent class analysis and 12-month follow-up.

Traditionally, low back-related leg pain (LBLP) is diagnosed clinically as referred leg pain or sciatica (nerve root involvement). However, within the spectrum of LBLP, we hypothesised that there may be other unrecognised patient subgroups. This study aimed to identify clusters of patients with LBLP using latent class analysis and describe their clinical course. The study population was 609 LBLP primary care consulters. Variables from clinical assessment were included in the latent class analysis. Characteristics of the statistically identified clusters were compared, and their clinical course over 1 year was described. A 5 cluster solution was optimal. Cluster 1 (n = 104) had mild leg pain severity and was considered to represent a referred leg pain group with no clinical signs, suggesting nerve root involvement (sciatica). Cluster 2 (n = 122), cluster 3 (n = 188), and cluster 4 (n = 69) had mild, moderate, and severe pain and disability, respectively, and response to clinical assessment items suggested categories of mild, moderate, and severe sciatica. Cluster 5 (n = 126) had high pain and disability, longer pain duration, and more comorbidities and was difficult to map to a clinical diagnosis. Most improvement for pain and disability was seen in the first 4 months for all clusters. At 12 months, the proportion of patients reporting recovery ranged from 27% for cluster 5 to 45% for cluster 2 (mild sciatica). This is the first study that empirically shows the variability in profile and clinical course of patients with LBLP including sciatica. More homogenous groups were identified, which could be considered in future clinical and research settings.