Mechanisms-based classifications of musculoskeletal pain: part 1 of 3: symptoms and signs of central sensitisation in patients with low back (± leg) pain

As a mechanisms-based classification of pain 'central sensitisation pain' (CSP) refers to pain arising from a dominance of neurophysiological dysfunction within the central nervous system. Symptoms and signs associated with an assumed dominance of CSP in patients attending for physiotherapy have not been extensively studied. The purpose of this study was to identify symptoms and signs associated with a clinical classification of CSP in patients with low back (± leg) pain. Using a cross-sectional, between-subjects design; four hundred and sixty-four patients with low back (± leg) pain were assessed using a standardised assessment protocol. Patients' pain was assigned a mechanisms-based classification based on experienced clinical judgement. Clinicians then completed a clinical criteria checklist specifying the presence or absence of various clinical criteria. A binary logistic regression analysis with Bayesian model averaging identified a cluster of three symptoms and one sign predictive of CSP, including: 'Disproportionate, non-mechanical, unpredictable pattern of pain provocation in response to multiple/non-specific aggravating/easing factors', 'Pain disproportionate to the nature and extent of injury or pathology', 'Strong association with maladaptive psychosocial factors (e.g. negative emotions, poor self-efficacy, maladaptive beliefs and pain behaviours)' and 'Diffuse/non-anatomic areas of pain/tenderness on palpation'. This cluster was found to have high levels of classification accuracy (sensitivity 91.8%, 95% confidence interval (CI): 84.5-96.4; specificity 97.7%, 95% CI: 95.6-99.0). Pattern recognition of this empirically-derived cluster of symptoms and signs may help clinicians identify an assumed dominance of CSP in patients with low back pain disorders in a way that might usefully inform their management.     

Mechanisms-based classifications of musculoskeletal pain: part 2 of 3: symptoms and signs of peripheral neuropathic pain in patients with low back (± leg) pain

As a mechanisms-based classification of pain 'peripheral neuropathic pain' (PNP) refers to pain arising from a primary lesion or dysfunction in the peripheral nervous system. Symptoms and signs associated with an assumed dominance of PNP in patients attending for physiotherapy have not been extensively studied. The purpose of this study was to identify symptoms and signs associated with a clinical classification of PNP in patients with low back (± leg) pain. Using a cross-sectional, between-subjects design; four hundred and sixty-four patients with low back (± leg) pain were assessed using a standardised assessment protocol. Patients' pain was assigned a mechanisms-based classification based on experienced clinical judgement. Clinicians then completed a clinical criteria checklist specifying the presence or absence of various clinical criteria. A binary logistic regression analysis with Bayesian model averaging identified a cluster of two symptoms and one sign predictive of PNP, including: 'Pain referred in a dermatomal or cutaneous distribution', 'History of nerve injury, pathology or mechanical compromise' and 'Pain/symptom provocation with mechanical/movement tests (e.g. Active/Passive, Neurodynamic) that move/load/compress neural tissue'. This cluster was found to have high levels of classification accuracy (sensitivity 86.3%, 95% CI: 78.0-92.3; specificity 96.0%, 95% CI: 93.4-97.8; diagnostic odds ratio 150.9, 95% CI: 69.4-328.1). Pattern recognition of this empirically-derived cluster of symptoms and signs may help clinicians identify an assumed dominance of PNP mechanisms in patients with low back pain disorders in a way that might usefully inform subsequent patient management.     

Self-reported pain severity, quality of life, disability, anxiety and depression in patients classified with 'nociceptive', 'peripheral neuropathic' and 'central sensitisation' pain. The discriminant validity of mechanisms-based classifications of low back (±leg) pain

Evidence of validity is required to support the use of mechanisms-based classifications of pain clinically. The purpose of this study was to evaluate the discriminant validity of ‘nociceptive’ (NP), ‘peripheral neuropathic’ (PNP) and ‘central sensitisation’ (CSP) as mechanisms-based classifications of pain in patients with low back (±leg) pain by evaluating the extent to which patients classified in this way differ from one another according to health measures associated with various dimensions of pain.This study employed a cross-sectional, between-subjects design. Four hundred and sixty-four patients with low back (±leg) pain were assessed using a standardised assessment protocol. Clinicians classified each patient’s pain using a mechanisms-based classification approach. Patients completed a number of self-report measures associated with pain severity, health-related quality of life, functional disability, anxiety and depression. Discriminant validity was evaluated using a multivariate analysis of variance.There was a statistically significant difference between pain classifications on the combined self-report measures, (p = .001; Pillai’s Trace = .33; partial eta squared = .16). Patients classified with CSP (n = 106) reported significantly more severe pain, poorer general health-related quality of life, and greater levels of back pain-related disability, depression and anxiety compared to those classified with PNP (n = 102) and NP (n = 256). A similar pattern was found in patients with PNP compared to NP.Mechanisms-based pain classifications may reflect meaningful differences in attributes underlying the multidimensionality of pain. Further studies are required to evaluate the construct and criterion validity of mechanisms-based classifications of musculoskeletal pain.     

Mechanical or inflammatory low back pain. What are the potential signs and symptoms?

Non-specific low back pain (NSLBP) is commonly conceptualised and managed as being inflammatory and/or mechanical in nature. This study was designed to identify common symptoms or signs that may allow discrimination between inflammatory low back pain (ILBP) and mechanical low back pain (MLBP). Experienced health professionals from five professions were surveyed using a questionnaire listing 27 signs/symptoms. Of 129 surveyed, 105 responded (81%). Morning pain on waking demonstrated high levels of agreement as an indicator of ILBP. Pain when lifting demonstrated high levels of agreement as an indicator of MLBP. Constant pain, pain that wakes, and stiffness after resting were generally considered as moderate indicators of ILBP, while intermittent pain during the day, pain that develops later in the day, pain on standing for a while, with lifting, bending forward a little, on trunk flexion or extension, doing a sit up, when driving long distances, getting out of a chair, and pain on repetitive bending, running, coughing or sneezing were all generally considered as moderate indicators of MLBP. This study identified two groups of factors that were generally considered as indicators of ILBP or MLBP. However, none of these factors were thought to strongly discriminate between ILBP and MLBP.     

Do within-session changes in pain intensity and range of motion predict between-session changes in patients with low back pain?

Physiotherapists commonly use post-treatment changes in a patient's pain intensity and range of motion to guide treatment selection and predict possible longer-term outcomes. This study tested the validity of this practice by evaluating the predictive value of within-session changes in pain intensity and range of motion in 53 patients with low back pain. Pain intensity and range of motion measurements of spinal flexion, extension, lateral flexion, and straight-leg-raise were taken by the patient's therapist before and after one treatment session, and were repeated by a blinded therapist at the beginning of the patient's subsequent treatment session. Regression analysis revealed that the strength of association between within-session and between-session changes ranged from r = 0.35 to r = 0.80 for range of motion measurements, and from r = 0.24 to r = 0.47 for pain intensity. Odds ratios for pain and range of motion ranged from 3.5 (95% CI 0.9 to 14.6) to 37.0 (95% CI 4.1 to 330), indicating greater odds of improving between-session if improvement was obtained within-session. These results provide preliminary support for the practice of using within-session changes in pain intensity and range of motion to guide treatment selection when treating impairments in patients with low back pain.     

Which psychosocial factors are related to severe pain and functional limitation in patients with low back pain?: Psychosocial factors related to severe low back pain

BackgroundLow back pain (LBP) is a global public health issue. Psychosocial factors are linked to LBP. However, there is a lack of knowledge about the relation of psychosocial factors to clinical outcomes of patients with severe LBP.ObjectiveTo investigate the relationship between specific psychosocial factors with severe pain and functional limitation of patients with LBP.MethodsA cross-sectional study of 472 participants with LBP was conducted. Participants completed self-reported questionnaires, including psychosocial factors, characteristics of pain, and functional limitations. Two multivariable logistic regression models were performed with severe pain intensity (≥ 7 out of 10) and functional limitation (≥ 7 out of 10) (dependent variables) and 15 psychosocial factors (independent variables).ResultsOne hundred twenty-five (26.5%) participants had severe LBP. Patients with catastrophising symptoms were 2.21 [95%Confidence Interval (CI): 1.30, 3.77] times more likely to have severe pain and 2.72 (95%CI: 1.75, 4.23) times more likely to have severe functional limitation than patients without catastrophising symptoms. Patients with maladaptive beliefs about rest were 2.75 (95%CI: 1.37, 5.52) times more likely to present with severe pain and 1.72 (95%CI: 1.04, 2.83) times more likely to have severe functional limitation. Patients with kinesiophobia were 3.34 (95%CI: 1.36, 8.24) times more likely to present with severe pain, and patients with social isolation were 1.98 (95%CI: 1.25, 3.14) times more likely to have severe functional limitation.ConclusionCatastrophising, kinesiophobia, maladaptive beliefs about rest, and social isolation are related to unfavourable clinical outcomes of patients with LBP.     

Is physical functioning influenced by activity-related pain prediction and fear of movement in patients with subacute low back pain?

In patients with low back pain (LBP), physical functioning may be negatively influenced by both expectations on pain and pain-related fear. It is unclear whether these factors influence both physical functioning in the laboratory as well as in daily life. The aim of this study was to test if a combination of persistent overprediction of pain and fear of movement predicts lab-based performance and whether these factors are relevant for predicting daily-life functioning.One hundred and twenty four patients with subacute LBP performed a laboratory-based performance test twice. Maximum voluntary contraction, pre-test pain expectations, perceived pain during testing and fear of movement were measured. Patients were classified as correct or incorrect predictors, based on differences between expected and perceived pain on the second attempt. Next, physical activity in daily life was measured with an accelerometer.In explaining physical functioning in the laboratory and in daily life an interaction effect between fear and pain prediction was observed. In overpredictors, fear was negatively associated with lab-based performance (β = ?0.48, p < 0.01), and positively associated with daily-life functioning (β = 0.50, p < 0.05). No significant association between fear and performance or daily-life functioning were found in correct predictors.In contrast to correct predictors, in overpredictors lab-based performance and daily-life functioning was additionally explained by fear of movement. Thus it appears that fear of movement is only predictive of performance in patients with LBP who simultaneously overpredict the consequences of movements in terms of painfulness.     

Do patients with low back pain and central sensitization have differences in physical fitness?

IntroductionLow back pain is one of the main musculoskeletal complaints, and may be associated with central sensitization (CS). The physical capacity of patients with low back pain and CS is not very clear.MethodsA cross-sectional study, with 92 patients divided into two groups according to their risk of CS. The patient's physical capacity ability was assessed using 6-min walking test (6MWT); timed up and go test (TUG); sit-to-stand test (STS); and trunk flexor, extensor and side-bridge endurance tests. In addition, participants completed questionnaires regarding disability, kinesiophobia, catastrophization and quality of life.ResultsThe group with a higher risk of CS had worst performance in the 6MWT (U = 1248; p < 0.001), STS (t(83) = 3.63; p < 0.001) and TUG (t(83) = −4.46; p < 0.001). Similarly, endurance in the right (U = 1453,5; p = 0,002) and left (U = 1467; p = 0,003) side-bridge tests, and the trunk extensor test (U = 1546; p = 0,003) was worse. Disability (U = 1272; p < 0.001), physical capacity kinesiophobia (t(83) = -2.21; p = 0.03) work kinesiophobia (U = 1452; p < 0.001), and pain catastrophization (t(77.57) = -5.03; p < 0.001), were also higher in the group with a higher risk of CS. Quality of life indicators were worse in the higher risk group for all domains of the EQ-5D-3L: Mobility (X²(1) = 12.92; p < 0.001), self-care (X²(1) = 16,3; p = 0,012), usual activities (X²(2) = 14.14; p = 0.001), pain (X²(2) = 27.79; p < 0.001), anxiety and depression (X²(2) = 15.05; p = 0.001).ConclusionPatients with low back pain and higher risks of CS appear to show lower performance in physical capacity tests, higher rates of disability, kinesiophobia, pain catastrophization, and lower quality of life compared to those with lower risks of CS.     

Reconditioning in groups: an effective programme for the rehabilitation of patients with low back pain?]

The article reports on a study in which elements of a group-oriented reconditioning programme for patients with low back pain were incorporated into the routine of an in-patient orthopaedic rehabilitation clinic. The specific elements of the new programme consisted of stable group structures during the whole stay of 3 to 4 weeks, and of 3 to 7 hrs. walks in hilly ground three times a week. The effects of this programme were tested against a standard programme with a mix of passive and active elements using a controlled study design. 92 persons participated in an experimental group and 81 persons in a control group with no significant differences found between the two groups at admission. Effects were measured by means of a physicians' questionnaire and a multidimensional patients' questionnaire (IRES) answered at admission, at discharge, and at six- and twelve-month follow-up. The results of a two-factorial analysis of variance with repeated measures showed that the interaction between group and time on the summary score of the IRES was not significant, although the experimental group showed somewhat better effects at all times of measurement. The discussion focuses on the reasons for this result, among which the unexpectedly good effects in the control group are named, as well as certain difficulties with the implementation of a strongly activity-oriented programme into the course of a "normal" rehabilitation clinic.     

How effective is the acute low back pain screening questionnaire for predicting 1-year follow-up in patients with low back pain?

OBJECTIVES: The aim of this study was to investigate potential associations between the Acute Low Back Pain Screening Questionnaire (ALBPSQ), a biopsychosocial screening instrument for identifying patients at risk of chronicity, and relevant variables at 1-year follow-up in a cohort of patients with low back pain. STUDY DESIGN: A 1-year prospective study was conducted in which patients who had previously received treatment in the Northern Ireland National Health Service (n = 118) were requested to complete a follow-up questionnaire package of pain and functional disability measures and a patient-centered questionnaire of seven variables considered relevant from the patient's perspective. PATIENTS: Ninety patients (76% response rate) returned the completed questionnaire package. RESULTS: The ALBPSQ total score and cutoff score of 112 were significantly positively associated with the pain and functional disability questionnaire scores at follow-up but did not significantly discriminate for difference scores on these measures. Although six of the seven patient-centered variables were significantly associated with the screening questionnaire total score, the cutoff score was strongly predictive of only one variable (work loss) and failed to demonstrate high levels of sensitivity for other variables (i.e., medication use, additional treatment, poor exercise participation). CONCLUSIONS: The findings of this study demonstrate that scores on the ALBPSQ were positively correlated with patients' levels of pain and functional disability at 1-year follow-up and correctly classified all patients reporting some degree of work loss but had minimal predictive strength for the other patient-centered variables evaluated.     

Is low back pain part of a general health pattern or is it a separate and distinctive entity? A critical literature review of comorbidity with low back pain

INTRODUCTION: Research concerning the development of low back pain (LBP) has traditionally focused on risk factors in search of explanations. This review focuses on comorbidity as a first step in identifying a frail subpopulation with a higher risk of developing low back pain, in particular persistent low back pain. Research into comorbidity might yield a greater understanding of the underlying mechanism for low back pain.Data sources Medline was searched from the beginning of the data base to December 2000, followed by a search through the authors' personal collections of epidemiologic literature regarding low back pain. All articles written in English were included if they related LBP to at least one other physical disorder. Articles were excluded if the prevalence of such disorders could not be compared to that of a control group or to the expected prevalence in a normal population.Data extraction The retrieved articles were evaluated for quality based on predefined methodological criteria, whereupon information about associations between low back pain and other physical disorders was extracted. RESULTS: Twenty-three articles were included. They showed positive associations to all disorders investigated (headache/migraine, respiratory disorders, cardiovascular disease, general health, and others) with the exception of diabetes. There was very little information regarding temporality, therefore there are no clues as to causal mechanisms. CONCLUSION: The literature leaves no doubt that diseases cluster in some individuals and that low back pain is part of this pattern. However, the nature of the relationship between low back pain and other disorders is still unclear.     

Health care providers communicate less well with patients with chronic low back pain – A study of encounters at a back pain clinic in Denmark

We aimed to study the quality of communication between health care providers and patients with low back pain with emphasis on information giving in a back pain clinic, including if characteristics of patients could be associated with communication quality. We videotaped 79 encounters in which 21 providers informed patients about the results of magnetic resonance imaging of the back. Background information about the patients was collected by questionnaires and interview after the encounter. Videotapes were analysed with the Four Habits Coding Scheme (4HCS) in which higher scores mean better communication. There were strong negative correlations between 4HCS scores and the duration of back pain, and patient age. The results were significant for all professional subgroups (doctors, physiotherapists, chiropractors). Communication quality in encounters with back pain patients is worse, the longer the patient has suffered pain. Poor communication quality also seems to be associated with patients being older.     

Can demographic and anthropometric characteristics predict clinical improvement in patients with chronic non-specific low back pain?

Objective

To identify potential prognostic factors that may predict clinical improvement of patients treated with different physical therapy interventions in the short-term.

Problem-solving in physiotherapy – physiotherapists’ talk about encounters with patients with non-specific low back pain

Purpose: To investigate how physiotherapists talk about the choice of intervention for patients with NSLBP, particularly how professionals manage clinical encounters that may be experienced as challenging. Method: Discourse analysis was performed of four focus groups’ talk. Twenty-one experienced physiotherapists working in primary health care in southern Sweden participated. Results: Four focal themes appeared: Responsibility for health and health-related problems; Normalization – what counts as a normal back pain problem in relation to living an ordinary life; Change process – how to lead one’s life; and Individualization of the intervention in relation to the individual patient but also from the physiotherapists’ point of view. The themes shape an over-arching pattern of Problem-solving – which concerned both the professional task and the back pain problem, and was related to varying case complexity. This may have implications for the intervention the individual patient will be offered and on outcome. Conclusions: Physiotherapists’ attitudes and approaches seem to entail components of professional and personal values which may influence patients’ access to health care, with a risk for unequal assessment and intervention as a consequence. We argue that enhanced physiotherapist-patient collaboration, including patient-led problem-investigation, is a prerequisite for improved outcome in terms of patient satisfaction, and for physiotherapy development. Future investigations of patients’ roles in specific face-to-face encounters are needed.

Implications for Rehabilitation

• Varying attitudes among professionals regarding responsibility for health and health-related problems may influence patients’ access to rehabilitation, with a risk for unequal assessment and intervention as a consequence.

• Professionals’ use of personal approaches indicates that interventions may be based on professional instead of patient preferences, with consequences on patient satisfaction and outcome.

• Enhanced professional-patient collaboration which thoroughly includes patient preferences seems to be a prerequisite for improved clinical outcome in terms of patient satisfaction, and for professional development.

     

Dose or content? Effectiveness of pain rehabilitation programs for patients with chronic low back pain: A systematic review

We sought to systematically analyze the influence of dose of pain rehabilitation programs (PRPs) for patients with chronic low back pain (CLBP) on disability, work participation, and quality of life (QoL). Literature searches were performed in PubMed, Cochrane Library, Cinahl, and Embase up to October 2012, using MeSH terms, other relevant terms and free-text words. Randomized controlled trials in English, Dutch, and German, analyzing the effect of PRPs, were included. One of the analyzed interventions had to be a PRP. Outcomes should be reported regarding disability, work participation, or QoL. To analyze dose, the number of contact hours should be reported. Two reviewers independently selected titles, abstracts, and full-text articles on the basis of inclusion and exclusion criteria. Data were extracted and risk of bias was assessed. Effect sizes (ES) were calculated for each intervention, and influence of dose variables was analyzed by a mixed model analysis. Eighteen studies were identified, reporting a wide variety of dose variables and contents of PRPs. Analyses showed that evaluation moment, number of disciplines, type of intervention, duration of intervention in weeks, percentage of women, and age influenced the outcomes of PRPs. The independent effect of dose variables could not be distinguished from content because these variables were strongly associated. Because dose variables were never studied separately or reported independently, we were not able to disentangle the relationship between dose, content, and effects of PRPs on disability, work participation, and QoL.     

Validation of a French version of Roland–Morris questionnaire in chronic low back pain patients

ObjectiveTo validate a French version of the Roland–Morris Disability Questionnaire (RMDQ) in patients with chronic low back pain (LBP).Material and methodsFifty-eight patients due to participate in a functional rehabilitation programme for chronic low back pain were included prospectively. The RMDQ, the Quebec Back Pain Disability Scale (QBPDS) and the “daily activities” subscale of the Dallas Pain Questionnaire (DPQ) were administered. The RMDQ was assessed for internal consistency, reliability, criterion validity and sensitivity to change.ResultsCronbach's alpha for the RMDQ was 0.84. The intraclass correlation coefficient [95% confidence interval] was 0.89 [0.83–0.93]. The RMDQ score was correlated with the QBPDS score (r = 0.713) and the DPQ's “daily activities” subscore (r = 0.514). The results of assessments before and after functional rehabilitation showed that the French version of the RMDQ had very high sensitivity to change (effect size: 1.49) and was more sensitive than the QBPDS and the DPQ's “daily activities” subscore.ConclusionsOur study validated the French version of the RMDQ in patients suffering from chronic low back pain. Furthermore, we highlighted the questionnaire's very high sensitivity to change.