Identifying Subgroups of Patients With Chronic Nonspecific Low Back Pain Based on a Multifactorial Approach: Protocol For a Prospective Study

Background

Low back pain, especially nonspecific chronic low back pain (LBP), the leading cause of disability worldwide, represents both social and economic problems. Different therapeutic management techniques can be used, but their effects vary. Clinicians and researchers attribute the variation in the efficacy of therapeutic and management techniques to the heterogeneity of the nonspecific chronic low back pain population, and they agree that nonspecific chronic LBP must be subgrouped.

Objective

This study aims to identify nonspecific chronic LBP subgroups based on a multifactorial approach, including biomechanical, physical, and psychosocial data.

Methods

A total of 100 nonspecific chronic LBP patients and 30 healthy participants aged between 18 and 60 years will be recruited for this prospective study. A psychosocial profile will be established using questionnaires on anxiety, depression, functional disability, pain, fear of pain, avoidance belief, and physical activity. A physical capacity evaluation will be conducted. It will evaluate flexibility of the hips, lumbar spine, and lateral thoracolumbar segment, as well as trunk (extensor and flexor) muscle endurance. The subjects will perform functional daily life activities, such as walking, object lifting, forward bending, sit-to-stand, stand-to-sit, balance, and usual postures. Full body kinematics, kinetics, and surface electromyography of the trunk and hip muscles will be assessed during these tasks. The clustering classification methods for the statistical analysis will be determined according to the data and will be used to identify the subgroups of nonspecific chronic LBP patients.

Results

Data collection started in September 2017 and will be completed with the inclusion of all the participants (100 nonspecific chronic LBP and 30 control). The study results will be published in peer-reviewed journals and presented at relevant international conferences.

Conclusions

Numerous studies have showed that the therapeutic management of nonspecific chronic LBP is difficult and has inconstant effects caused by the complexity and heterogeneity of nonspecific chronic LBP. Identifying subgroups with a multifactorial approach is more comprehensive and closer to the pathophysiology of nonspecific chronic LBP. It also represents benefit interests and a challenge both clinically and socially. The perspective of this study is expected to support clinicians for a more adapted therapeutic management for each subgroup.

Clinical classification criteria for radicular pain caused by lumbar disc herniation: the radicular pain caused by disc herniation (RAPIDH) criteria

BACKGROUND CONTEXT

Classification criteria are recommended for diseases that lack specific biomarkers to improve homogeneity in clinical research studies. Because imaging evidence of lumbar disc herniations (LDHs) may not be associated with symptoms, clinical classification criteria based on patient symptoms and physical examination findings are required.

PURPOSE

This study aimed to produce clinical classification criteria to identify patients with radicular pain caused by LDH.

STUDY DESIGN

The study design was a two-stage process. Phase 1 included a Delphi process and Phase 2 included a cohort study.

PATIENT SAMPLE

The patient sample included outpatients recruited from spine clinics in five countries.

OUTCOME MEASURES

The outcome measures were items from history and physical examination.

MATERIALS AND METHODS

In Phase 1, 17 spine experts participated in a Delphi process to select symptoms and signs suggesting radicular pain caused by LDH. In Phase 2, 19 different clinical experts identified patients they confidently classified as presenting with (1) radicular pain caused by LDH, (2) neurogenic claudication (NC) caused by lumbar spinal stenosis, or (3) non-specific low back pain (NSLBP) with referred leg pain. Patients completed survey items and specialists documented examination signs. A score to predict radicular pain caused by LDH was developed based on the coefficients of the multivariate model. An unrestricted grant of less than US$15,000 was received from MSD: It was used to support the conception of the Delphi, data management, and statistical analysis. No fees were allocated to participating spine specialists.

RESULTS

Phase 1 generated a final list of 74 potential symptoms and signs. In Phase 2, 209 patients with pain caused by LDH (89), NC (63), or NSLBP (57) were included. Items predicting radicular pain caused by LDH (p<.05) were monoradicular leg pain distribution, patient-reported unilateral leg pain, positive straight leg raise test <60° (or femoral stretch test), unilateral motor weakness, and asymmetric ankle reflex. The score had an AUC of 0.91. An easy-to-use weighted set of criteria with similar psychometric characteristics is proposed (specificity 90.4%, sensitivity 70.6%).

CONCLUSIONS

Classification criteria for identifying patients with radicular pain caused by LDH are proposed. Their use could improve the homogeneity of patients enrolled in clinical research studies.

[Spinal injection : risks and side effects]

The efficacy of spinal injection for chronic spinal pain is dubious for most conditions. They are however frequently prescribed. Side effects are poorly reported in the literature. In addition to benign and transient problems, serious and lethal side effects have been reported due to infection, hematoma or central and spinal cord infarctions which could be related to intravascular injection of corticoids. Although their frequency is excessively low, they should be discussed with every patient before prescription and should be mentioned in the consent form.

Modifying beliefs about back pain: A pilot study among healthcare professionals

OBJECTIVES

This study aimed to explore whether a preventive intervention based on the non-injury model and the biopsychosocial model of back pain succeeded in shifting beliefs toward less negative representations and in decreasing fear-avoidance beliefs related to back pain.

METHODS

One hundred and one healthcare professionals took part in a 10-h educational program held over 2 consecutive days, based on the key messages of the "Back Book." Baseline values were measured 6 weeks before the intervention and when it started. Follow-up was performed at the end of the intervention and six months later.

RESULTS

No significant changes were observed between baseline values and values measured at the beginning of the intervention, but participants' beliefs about LBP changed significantly after the program. The benefit remained at 6 months follow-up.

CONCLUSION

A prevention program based on the non-injury and bio-psychosocial models of LBP, introducing empowerment and problem-solving strategies, significantly reduced fear-avoidance and negative beliefs about LBP. The change was clinically relevant and thus could decrease direct and indirect healthcare costs.

[THE MALADAPTIVE BELIEFS OF PATIENTS WITH LOW BACK PAIN. A NARRATIVE REVIEW]

OBJECTIVE

to summarize the knowledge regarding the maladaptive beliefs of patients with non-specific low back pain.

METHODS

a narrative literature review on these beliefs was conducted by an international and multidisciplinary team of experts in the field.

RESULTS

these beliefs, which can result in negative consequences on functioning and on patient prognosis, have various origins: family and friends, media, previous experience and/or health care professionals' messages. The latter, who have a considerable and enduring influence, have the potential to change and correct the patients' misbeliefs; however, they can also reinforce them in case of inappropriate messages and attitudes. Informing and educating the patient (by means of reassurance, explanations of the non-systematic association pain-injury, encouragement to get and stay physically active) are the basis of treatment. Taking into account the consequences of some words which may be misinterpreted, the results of imaging should be wisely discussed with the patient. Pain neurophysiology education and cognitive behavioral therapy (i.a., in vivo graded exposure techniques) are effective additional treatments.

CONCLUSIONS

Misbeliefs are frequent in patient with low back pain. They do need to be looked for and corrected.

[Greater trochanteric pain syndrome]

Trochanteric bursitis, also known as "greater trochanter pain syndrome", is a frequent and often under-diagnosed cause of pain in the lateral hip region. The diagnosis is essentially based on the clinical examination; however various forms of imaging may be useful to confirm the diagnosis and particularly to ex- clude other aetiologies. The different therapeutic options include non-steroidal anti-inflammatories, physiotherapy, local injections of cortisone and local anaesthetic, and extra-corporeal shock wave therapy. Surgical intervention is only indicated in rare cases.

Validity of the French version of the Core Outcome Measures Index for low back pain patients: a prospective cohort study

PURPOSE

Among the many questionnaires available to evaluate low back pain (LBP) patients, the Core Outcome Measures Index (COMI) has the unique advantage to investigate five dimensions using seven short questions. The aim of this study was to explore additional properties of the questionnaire in a French-speaking non-surgical population.

METHODS

This study was conducted on 168 patients suffering from subacute or chronic LBP and followed up for 6 months in three French-speaking countries. In addition to basic psychometric properties (e.g., construct validity, floor and ceiling effect, reproducibility), internal validity was analyzed by a factor analysis using Cronbach's alpha. Responsiveness and sensitivity to change were assessed through minimal detectable change (MDC), effect size, and Minimal Clinically Important Improvement (MCII). We used an anchor-based method with receiver operating characteristic (ROC) curve analysis to assess MCII and the Patient Acceptable Symptom State.

RESULTS

Construct validity, reliability (Cronbach's alpha = 0.87), reproducibility and the absence of floor and ceiling effects were confirmed. Factor analysis indicated a one-dimensional construct that validates the use of a sum score. The MDC (2.1) was inferior to the MCII (2.3). The limit below which the patient claims to be in a fair condition (Patient Acceptable Symptom State) was set at 3.

CONCLUSIONS

The COMI is a self-report questionnaire with the capacity to easily and quickly explore several dimensions in patients with LBP that can be then summarized in a meaningful sum score. Additional knowledge provided by our study should encourage the widespread use of the COMI among the spine community.

[Inter-hospital CHUV-HUG medical consensus of back pain management. Its application in care pathways within CHUV of Lausanne]

Back pain is a considerable economical burden in industrialised countries. Its management varies widely across countries, including Switzerland. Thus, the University Hospital and University of Lausanne (CHUV) recently improved intern processes of back pain care. In an already existing collaborative context, the two university hospitals in French-speaking Switzerland (CHUV, University Hospital of Geneva), felt the need of a medical consensus, based on a common concept. This inter-hospital consensus produced three decisional algorithms that bear on recent concepts of back pain found in literature. Eventually, a fast track was created at CHUV, to which extern physicians will have an organised and rapid access. This fast track aims to reduce chronic back pain conditions and provides specialised education for general practitioners-in-training.

Added value of an intensive multidisciplinary functional rehabilitation programme for chronic low back pain patients

BACKGROUND

Several treatments exist for chronic low back pain (cLBP) patients although none has shown superiority. Among group treatments, muscle reconditioning programmes (MRPs) are the most commonly used. Multidisciplinary functional rehabilitation programmes (MFRPs) are an alternative.

OBJECTIVE

To compare a MFRP with a MRP as few studies compare these treatments

METHODS

This was a prospective, nonrandomised, controlled study comparing cLBP patients participating in a MRP or MFRP in an outpatient setting. The predetermined primary outcome measure was the daily life activity subscale (DLA) of the Dallas Pain Questionnaire (DPQ) within one year after the end of the treatment.

RESULTS

Twenty-one patients were included in the MRP and 24 in the MFRP. At inclusion, the groups were similar in terms of age (mean 40 years), sex (50%-60% males), sick leave duration (mean 6.0 months, standard deviation (SD) 4.4 months) and follow up (mean 9.0 months, SD 2.0 months). The DLA score decreased from 59.5% (SD 16.9) to 44.8% (SD 25.4), p <0.01, in the MFRP and from 62.3 (SD 20.3) to 58.8 (SD 20.7), p = 0.3, in the MRP. The between-groups difference at follow-up was 13.8, p = 0.05, and the difference in the mean improvement was -11.5 (5.9), p = 0.058. Seventy-eight percent of MFRP patients versus 47 % in the MRP group returned to work (p = 0.08).

DISCUSSION

In a population of highly disabled cLBP patients, MFRP seems more effective in increasing function and return to work. Interpretation is limited by the small population included and by the type of trial.

CONCLUSION

Randomised studies are needed to confirm these results and explore the cost-effectiveness of MFRP.

Effectiveness of preventive back educational interventions for low back pain: a critical review of randomized controlled clinical trials

PURPOSE

A systematic search was conducted to study the efficiency of preventive educational interventions mainly focused on a biomechanical/biomedical model.

METHODS

The PubMed electronic database and the Cochrane Library were searched based on a combination of keywords related to low back pain (LBP) and posture education. Only randomized controlled trial (RCT) studying the efficiency on outcomes directly related to LBP of a preventive intervention programme mainly based on education of proper care of the back for subjects not seeking treatment were included. References of the articles meeting these inclusion criteria were also checked to identify other potential citations. Besides, a methodological study assessment of the included RCTs was performed.

RESULTS

Nine studies, all conducted at the workplace were included in this review. Their mean quality level was low (5.1/12) and among the four studies with a huge sample size (n > 400 subjects), only one had an acceptable methodological quality score (6/12). The education interventions differed widely from one study to another. No significant differences between the control and education groups were found at the follow-up in eight out of the nine studies on the incidence of back pain, disability and sick leave.

CONCLUSIONS

The results of the RCTs included in this review suggest that educational interventions mainly focused on a biomechanical/biomedical model are not effective in preventing LBP. However, taking into account the methodological quality level of the RCTs as well as the very short and heterogeneous interventions often proposed, additional high-quality studies with a longer education period are needed to conclude that such interventions are inefficient.

[Spinal stenosis: diagnosis and treatment]

Spondylotic cervical myelopathy (SCM) is a radiologic entity that can match a clinical syndrome of varying degree of severity, and results from spinal canal narrowing due to physiological degeneration of the cervical spine. Clinically, cervical spinal canal narrowing can produce minimal symptoms such as non-specific neck pain, foraminal entrapment of nerve roots, or more severe, chronic myelopathy. SCM initially manifests by signs of posterior medullary tract dysfunction with subsequent pallesthesia, resulting in gait and balance disturbance. Spasticity due to lower motoneurone impairment and incontinence may appear in later stages. Once the symptoms of myelopathy occur, functional deterioration will take place sooner or later. Surgery can then be recommended and scheduled according to the severity of functional impairment and imaging.

[Postural hygiene and ergonomic advices for low back pain: rethinking our practice]

In recent years, scientific understanding of low back pain has increased considerably, sometimes shoving concepts thought to be unshakable. If we consider postural hygiene,whose techniques were conceptualized in the 70's and are still widely used, not only some axioms were not confirmed but some evidences suggest that it may sometimes have deleterious effects. After reviewing these elements it appears that there is no simple formula applicable to all patients with low back pain. Instead we offer food for thought so that every therapist can adapt his practice on an individual basis.

[Lumbar spinal stenosis: clinical course, pathophysiology and treatment]

The lumbar spinal stenosis is a radiological description of a pathology that can present clinically by a neurogenic intermittent claudication; its diagnosis is mainly clinical. After listing the main criteria allowing the clinician to make a diagnosis, a review of available treatments is proposed. There are few quality studies and an empirical approach is often necessary. In severe cases, very disabling despite correct treatment, a surgical approach may be considered and discussed with the patient to avoid failure, sometimes linked to excessive expectations.

[Interdisciplinary treatment of chronic low back pain: psychological aspects and personality traits]

Evidence on chronic low back pain treatments stresses the need for a multidimensional approach that aims a biopsychosocial rehabilitation. The caregiver team of the rheumatology division of the University Hospitals of Geneva has successfully applied this approach over the last years and this article emphasizes the value of a close collaboration with the division of liaison psychiatry. The use of cognitive-behavioral and psycho-educational techniques guaranties the definition of patient-centred and measurable treatment objectives. The inclusion of a psychotherapy group promotes free expression and sharing of psychological distress. Assessment of personality traits allows for considering the global nature of the patients rather than merely aiming the normalization of their deviant aspects.

[Use of glucocorticoids in low back pain due to disc herniation with radicular involvement]

Although systemic glucocorticoids are frequently used for the treatment of radicular pain due to disc herniation, there are only few studies available. No trial has successfully demonstrated the superiority of systemic glucocorticoids compared to placebo. Therefore their use is not recommended. Spinal injection using radiographic guidance appears to provide some beneficial short-term effect on pain. It might be offered when pain treatments according to the WHO steps have failed. Because rare but serious adverse events have been reported, transforaminal periradicular injections should only be used after thorough analysis of risks and benefits with the patient.

Adalimumab in acute sciatica reduces the long-term need for surgery: a 3-year follow-up of a randomised double-blind placebo-controlled trial

INTRODUCTION

Two subcutaneous injections of adalimumab in severe acute sciatica significantly reduced the number of back operations in a short-term randomised controlled clinical trial.

OBJECTIVE

To determine in a 3-year follow-up study whether the short-term benefit of adalimumab in sciatica is sustained over a longer period of time.

METHODS

The primary outcome of this analysis was incident discectomy. Three years after randomisation, information on surgery could be retrieved in 56/61 patients (92%).A multivariate Cox proportional hazard models, adjusted for potential confounders, was used to determine factors predisposing to surgery.

RESULTS

Twenty-three (41%) patients had back surgery within 3 years, 8/29 (28%) in the adalimumab group and 15/27 (56%) in the placebo group, p=0.04. Adalimumab injections reduced the need for back surgery by 61% (HR)=0.39 (95% CI 0.17 to 0.92). In a multivariate model, treatment with a tumour necrosis factor-α antagonist remained the strongest protective factor (HR=0.17, p=0.002). Other significant predictors of surgery were a good correlation between symptoms and MRI findings (HR=11.6, p=0.04), baseline intensity of leg pain (HR=1.3, p=0.06), intensity of back pain (HR=1.4, p=0.03) and duration of sickness leave (HR=1.01 per day, p=0.03).

CONCLUSION

A short course of adalimumab in patients with severe acute sciatica significantly reduces the need for back surgery.

Reliability and validity of the cross-culturally adapted French version of the Core Outcome Measures Index (COMI) in patients with low back pain

PURPOSE

To conduct a cross-cultural adaptation of the Core Outcome Measures Index (COMI) into French according to established guidelines.

METHODS

Seventy outpatients with chronic low back pain were recruited from six spine centres in Switzerland and France. They completed the newly translated COMI, and the Roland Morris disability (RMQ), Dallas Pain (DPQ), adjectival pain rating scale, WHO Quality of Life, and EuroQoL-5D questionnaires. After ~14 days RMQ and COMI were completed again to assess reproducibility; a transition question (7-point Likert scale; "very much worse" through "no change" to "very much better") indicated any change in status since the first questionnaire.

RESULTS

COMI whole scores displayed no floor effects and just 1.5% ceiling effects. The scores for the individual COMI items correlated with their corresponding full-length reference questionnaire with varying strengths of correlation (0.33-0.84, P < 0.05). COMI whole scores showed a very good correlation with the "multidimensional" DPQ global score (Rho = 0.71). 55 patients (79%) returned a second questionnaire with no/minimal change in their back status. The reproducibility of individual COMI 5-point items was good, with test-retest differences within one grade ranging from 89% for 'social/work disability' to 98% for 'symptom-specific well-being'. The intraclass correlation coefficient for the COMI whole score was 0.85 (95% CI 0.76-0.91).

CONCLUSIONS

In conclusion, the French version of this short, multidimensional questionnaire showed good psychometric properties, comparable to those reported for German and Spanish versions. The French COMI represents a valuable tool for future multicentre clinical studies and surgical registries (e.g. SSE Spine Tango) in French-speaking countries.

Development and validation of a questionnaire assessing volitional competencies to enhance the performance of physical activities in chronic low back pain patients

Background

Motivation has long been emphasized as the most important determinant of action. However, there is a substantial gap between people's goals and their attainment. Patients may be motivated and yet unable to take action if their volitional competencies are insufficient. One of the important tasks of volition is goal-maintenance. Research has stressed the importance of a volitional tool, the implementation intentions. Implementation intentions indicate where, when, and how the action leading to the goal will be performed. Forming implementation intentions favours the execution of goal-directed efforts, and reinforces the relationship between intentions and behaviours. Results from various studies clearly suggest that volitional competencies and implementation intentions could play a role in low back pain (LBP) patients. However, there is at present no questionnaire allowing assessing the capacity of implementation intentions of physical activities in LBP patients.

Methods/Design

This study will develop such a questionnaire, using a 3-step approach. A first qualitative step to build categories and generate items; 30 patients suffering chronic LBP will be invited to participate in semi-structured interviews; verbatim and derived items will then be submitted to a panel of experts, using a Delphi method; a second quantitative step to examine the properties of items, and determine the factorial structure of the questionnaire; 100 patients suffering chronic LBP will be recruited to respond to this phase; and third, preliminary psychometric analyses (item-scale correlations, construct validity, reliability); 180 chronic LBP patients will be recruited for this phase of the study. The relationships between implementation intentions and variables affecting physical activity on chronic LBP patients, i.e. pain, physical capacities, fear-avoidance beliefs, kinesiophobia, work status, and level of physical activity will be considered.

Discussion

Developing a questionnaire to assess implementation intentions would allow investigating the role of these intentions in the transition from acute to chronic LBP. The results of this study should contribute to the understanding of the psychological processes at stake in the development of chronic LBP, and in particular to the identification of factors eventually favouring patients' participation in and adherence to active physical treatments.