Physical activity as a prognostic factor of pain intensity and disability in patients with low back pain: A systematic review

Physical activity as mediator between back pain and disability

The objective was to explore the mediating role of leisure-time physical activity on the correlation between back pain and disability. A mediation analysis was conducted among the cross-sectional sample of 1330 patients in outpatient clinic. The average age was 47.6 years and 64% were women. For the entire sample, the mediating effect of physical activity remained below 10% of the total effect. The mediating effect was significantly greater among women comparing to men - up to 19.0% [95% confidence interval (CI) 10.4-27.6%] versus 2.3% (95% CI 0.0-6.1%). The effect did not significantly differ based on age, BMI, or educational or professional status. Some insignificant trends, however, could be seen - the effect was possibly stronger among patients with higher educational level and those with higher BMI. The results suggested that while physical activity seems to be a weak mediator, its mediating role might vary across different groups of patients with back pain. This variation should be taken into account when planning rehabilitation measures for people with back pain.

Management of low back pain and lumbosacral radicular syndrome: the Guideline of the Royal Dutch Society for Physical Therapy (KNGF)

BACKGROUND

Significant progress and new insights have been gained since the Dutch Physical Therapy guideline on low back pain (LBP) in 2013 and the Cesar en Mensendieck guideline in 2009, necessitating an update of these guidelines.

AIM

To update and develop an evidence-based guideline for the comprehensive management of LBP and lumbosacral radicular syndrome (LRS) without serious specific conditions (red flags) for Dutch physical therapists and Cesar and Mensendieck Therapists.

DESIGN

Clinical practice guideline.

SETTING

Inpatient and outpatient.

POPULATION

Adults with LBP and/or LRS.

METHODS

Clinically relevant questions were identified based on perceived barriers in current practice of physical therapy. All clinical questions were answered using published guidelines, systematic reviews, narrative reviews or systematic reviews performed by the project group. Recommendations were formulated based on evidence and additional considerations, as described in the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Evidence-to-Decision framework. Patients participated in every phase.

RESULTS

The guideline describes a comprehensive assessment based on the International Classification of Functioning, Disability and Health (ICF) Core Set for LBP and LRS, including the identification of alarm symptoms and red flags. Patients are assigned to three treatment profiles (low, moderate and high risk of persistent symptoms) based on prognostic factors for persistent LBP. The guideline recommends offering simple and less intensive support to people who are likely to recover quickly (low-risk profile) and more complex and intensive support to people with a moderate or high risk of persistent complaints. Criteria for initiating and discontinuing physical therapy, and referral to a general practitioner are specified. Recommendations are formulated for information and advice, measurement instruments, active and passive interventions and behavior-oriented treatment.

CONCLUSIONS

An evidence based physical therapy guideline for the management of patients with LBP and LRS without red flags for physical therapists and Cesar and Mensendieck therapists was developed. Cornerstones of physical therapy assessment and treatment are risk stratification, shared decision-making, information and advice, and exercises.

CLINICAL REHABILITATION IMPACT

This guideline provides guidance for clinicians and patients to optimize treatment outcomes in patients with LBP and LRS and offers transparency for other healthcare providers and stakeholders.

Biofeedback Sensor vs. Physiotherapist Feedback During Core Stabilization Training in Patients with Chronic Nonspecific Low Back Pain

Core stabilization training utilizes principles of motor learning to retrain control of the trunk muscles and lead to improvements in chronic non-specific low back pain (CNLBP). To compare the effects of biofeedback sensor and conventional physiotherapist (PT) feedback during core stabilization and activity training in patients with CNLBP. Thirty-eight patients with CNLBP were randomly assigned to Biofeedback (n = 19) or PT feedback (n = 19) groups. Patients continued 12 sessions of combined core stabilization and activity training. An auditory and tactile biofeedback was given using a validated tilt sensor integrated with an application in the Biofeedback group. An experienced PT provided verbal and tactile feedback to maintain the neutral position in the PT Feedback group. The outcomes were; disability (Revised Oswestry Disability Index-RODI), muscle activity (m.transversus abdominis and m.multifidus), pain (Visual Analog Scale-VAS), proprioception error of the trunk, patient beliefs (Fear Avoidance Beliefs Questionnaire-FABQ) and presence of depressive symptoms (Beck Depression Index-BDI), and quality of life (Short Form (SF)-36). The main effect of time were statistically significant on VAS, RODI, m.transversus abdominis and m.multifidus muscle activities, flexion, and extension proprioception error of the trunk, FABQ, BDI, and SF-36 scores in Biofeedback and PT feedback groups (p < 0.05 for all). The time X group interaction was significant on flexion and extension proprioception error of the trunk PT feedback group (consecutively; p = 0.004, p = 0.022). Biofeedback sensor or PT feedback during core stabilization training equally improves pain, disability, muscle activity, depressive symptoms, patient beliefs, and quality of life in patients with CNLBP.

Does the Number of Comorbidities Predict Pain and Disability in Older Adults With Chronic Low Back Pain? A Longitudinal Study With 6- and 12-Month Follow-ups

BACKGROUND AND PURPOSE

People who live longer often live with multimorbidity. Nevertheless, whether the presence of multimorbidity affects pain and disability in older adults with chronic low back pain (LBP) remains unclear. The aim of this study was to investigate whether multimorbidity predicts pain intensity and disability at 6- and 12-month follow-ups in older adults with chronic LBP.

METHODS

This was a prospective, longitudinal study with 6- and 12-month follow-ups. Participants with chronic LBP (age ≥ 60 years) were recruited and interviewed at baseline, 6 months, and 12 months. Self-reported measures included the number of comorbidities, assessed through the Self-Administered Comorbidity Questionnaire, pain intensity, assessed with the 11-point Numerical Rating Scale, and disability, assessed with the Roland-Morris Disability Questionnaire. Data were analyzed using univariate and multivariate regression models.

RESULTS AND DISCUSSION

A total of 220 participants were included. The number of comorbidities predicted pain intensity at 6-month (β= 0.31 [95% CI: 0.12 to 0.50]) and 12-month (β= 0.29 [95% CI: 0.08 to 0.50]) follow-ups. The number of comorbidities predicted disability at 6-month (β= 0.55 [95% CI: 0.20 to 0.90]) and 12-month (β= 0.40 [95% CI: 0.03 to 0.77]) follow-ups.

CONCLUSION

The number of comorbidities at baseline predicted pain and disability at 6-month and 12-month follow-ups in older adults with chronic LBP. These results highlight the role of comorbidities as a predictive factor of pain and disability in patients with chronic LBP, emphasizing the need for timely and continuous interventions in older adults with multimorbidity to mitigate LBP-related pain and disability.

The influence of intervertebral disc overloading on nociceptor calcium flickering

Introduction

Mechanical overloading can trigger a degenerative-like cascade in an organ culture of intervertebral disc (IVD). Whether the overloaded IVD can influence the activation of nociceptors (i.e., the damage sensing neurons) remains unknown. The study aims to investigate the influence of overloaded IVD conditioned medium (CM) on the activation of nociceptors.

Methods

In the static loading regime, force-controlled loading of 0.2 MPa for 20 h/day representing "long-term sitting and standing" was compared with a displacement-controlled loading maintaining original IVD height. In the dynamic loading regime, high-frequency-intensity loading representing degenerative "wear and tear" was compared with a lower-frequency-intensity loading. CM of differently loaded IVDs were collected to stimulate the primary bovine dorsal root ganglion (DRG) cultures. Calcium imaging (Fluo-4) and calcitonin gene-related peptide (CGRP) immunofluorescent labeling were jointly used to record the calcium flickering in CGRP(+) nociceptors.

Results

Force-controlled loading led to a higher IVD cell death compared to displacement-controlled loading. Both static and dynamic overloading (force-controlled and high-frequency-intensity loadings) elevated the frequency of calcium flickering in the subsurface space of CGRP(+) nociceptors compared to their mild loading counterparts.

Conclusion

In the organ culture system, IVD overloading mediated an altered IVD-nociceptor communication suggesting a biological mechanism associated with discogenic pain.

The Mediation Effect of Pain on the Relationship between Kinesiophobia and Lumbar Joint Position Sense in Chronic Low Back Pain Individuals: A Cross-Sectional Study

(1) Background: Fear of movement (kinesiophobia) and impaired lumbar joint position sense (LJPS) play a vital role in developing and maintaining non-specific chronic low back pain (CLBP). However, how kinesiophobia impacts LJPS is still being determined. The aims of this study are to (1) assess the correlation between kinesiophobia and LJPS in individuals with chronic low back pain; (2) compare LJPS between individuals with CLBP and those who are asymptomatic; and (3) evaluate if pain can mediate the relationship between kinesiophobia and LJPS in CLBP individuals. (2) Methods: Eighty-three individuals (mean age = 48.9 ± 7.5 years) with a diagnosis of CLBP and 95 asymptomatic individuals (mean age = 49.4 ± 7.0 years) were recruited into this cross-sectional study. Fear of movement in CLBP individuals was assessed using the Tampa Scale for Kinesiophobia (TSK). LJPS was determined using the active target repositioning technique using a dual-digital inclinometer. LJPS was evaluated in lumbar flexion, extension, and side-bending left and right directions, and the repositioning accuracy was determined in degrees using a dual digital inclinometer. (3) Results: Kinesiophobia showed a significant (p < 0.001) moderate positive correlation with LJPS (flexion: r = 0.51, extension: r = 0.41, side-bending left: r = 0.37 and side-bending right: r = 0.34). LJPS errors were larger in CLBP individuals compared to asymptomatic individuals (p < 0.05). Mediation analyses showed that pain significantly mediated the relationship between kinesiophobia and LJPS (p < 0.05) in CLBP individuals. (4) Conclusions: Kinesiophobia and LJPS were positively associated. LJPS is impaired in CLBP individuals compared to asymptomatic individuals. Pain may mediate adverse effects on LJPS. These factors must be taken into account when assessing and developing treatment plans for those with CLBP.

Biopsychosocial Factors for Chronicity in Individuals with Non-Specific Low Back Pain: An Umbrella Review

Low back pain (LBP) is a global and disabling problem. A considerable number of systematic reviews published over the past decade have reported a range of factors that increase the risk of chronicity due to LBP. This study summarizes up-to-date and high-level research evidence on the biopsychosocial prognostic factors of outcomes in adults with non-specific low back pain at follow-up. An umbrella review was carried out. PubMed, the Cochrane Database of Systematic Reviews, Web of Science, PsycINFO, CINAHL Plus and PEDro were searched for studies published between 1 January 2008 and 20 March 2020. Two reviewers independently screened abstracts and full texts, extracted data and assessed review quality. Fifteen systematic reviews met the eligibility criteria; all were deemed reliable according to our criteria. There were five prognostic factors with consistent evidence of association with poor acute-subacute LBP outcomes in the long term (high levels of pain intensity and disability, high emotional distress, negative recovery expectations and high physical demands at work), as well as one factor with consistent evidence of no association (low education levels). For mixed-duration LBP, there was one predictor consistently associated with poor outcomes in the long term (high pain catastrophism). We observed insufficient evidence to synthesize social factors as well as to fully assess predictors in the chronic phase of LBP. This study provides consistent evidence of the predictive value of biological and psychological factors for LBP outcomes in the long term. The identified prognostic factors should be considered for inclusion into low back pain explanatory models.

Vigorous regular leisure-time physical activity is associated with a clinically important improvement in back pain - a secondary analysis of randomized controlled trials

Background

Neck and back pain are musculoskeletal conditions with serious individual and societal consequences. Current evidence about the prognostic value for neck and back pain is limited and conflicting. This prospective cohort study aimed to assess the association between leisure-time physical activity (LPA) and improvement of neck and/or back pain in a working population receiving manual therapy or general care in one of two randomized controlled trials (RCTs).

Methods

Analyses of data from two RCTs evaluating the effect of manual therapies for neck and/or back pain was conducted. Participants (n = 1 464) answered questionnaires about frequency and effort level of LPA at baseline. LPA on moderate or vigorous levels was compared to no or low/irregular moderate and vigorous levels. Pain intensity was assessed with numerical scales at baseline and 3-, 6-, and 12-month follow-up. The outcome was minimal clinically important improvement in pain intensity, defined as ≥2 points improvement in mean pain intensity at follow-up. Crude- and adjusted risk ratios (RR) with 95% confidence intervals (CI) were calculated with Poisson regression analysis and stratified by pain location.

Results

Participants with neck and/or back pain performing vigorous LPA showed a minimal clinically important improvement after 12 months compared to the control group; RR 1.35 (95% CI; 1.06-1.73). No effect was observed at 3 or 6 months. Moderate LPA did not improve pain intensity in any follow-up. Stratified analyses revealed that the effect of vigorous LPA at 12 months in back pain was RR 1.83 (95% CI; 1.26-2.66) and neck pain RR 1.06 (95% CI; 0.75-1.49).

Conclusions

Persons with neck and/or back pain receiving manual therapy or general evidence-based care have greater chance of improvement after 12 months if they prior to treatment frequently practice vigorous LPA. When analyzed separately, the effect was only present for back pain.

Trial registration

Registration in Current Controlled Trials (ISRCTN), Stockholm Manual Intervention Trial (MINT), ISRCTN92249294 BJORN-trial, ISRCTN56954776

Effectiveness of stratified treatment for back pain in Danish primary care: A randomized controlled trial

Background

A randomized controlled trial (RCT) of stratified care demonstrated superior clinical outcomes and cost‐effectiveness for low back pain (LBP) patients in UK primary care. This is the first study in Europe, outside of the original UK study, to investigate the clinical efficacy and cost‐effectiveness of stratified care compared with current practice for patients with non‐specific LBP.

Methods

The study was a two‐armed RCT. Danish primary care patients with LBP were randomized to stratified care (n = 169) or current practice (n = 164). Primary outcomes at 3‐ and 12‐months' follow‐up were Roland Morris Disability Questionnaire (RDMQ), patient‐reported global change and time off work. Secondary outcomes included pain intensity, patient satisfaction, healthcare resource utilization and quality‐adjusted life years.

Results

Intention‐to‐treat analyses found no between‐group difference in RMDQ scores at 3 months (0.5, 95% CI −1.8 to 0.9) or 12 months (0.4, −2.1 to 1.3). No overall differences were found between the arms at 3 and 12 months with respect to time off work or secondary outcomes. Stratified care intervention resulted in significantly fewer treatment sessions (3.5 [SD 3.1] vs. 4.5 [3.5]) and significantly lower total healthcare costs (€) (13.4 [529] vs. 228 [830], p = .002). There was no difference in cost‐effectiveness (0.09, 0.05 to 0.13 vs. 0.10, 0.07–0.14, p = .70).

Conclusions

There was no significant difference in clinical outcomes between patients with non‐specific LBP receiving stratified care and those receiving current practice. However, stratified care may reduce total healthcare costs if implemented in Danish primary care.

Significance

Stratified care for low back pain based on risk profile is recommended by recent evidence based clinical guidelines. This study is the first broad replication of the STarT Back Trial in Europe. Therefore, the study adds to the body of knowledge evaluating the effectiveness of stratified care for low back pain in primary care, and provides insight into the effects of stratification on clinical practice.

Self-reported prognostic factors in adults reporting neck or low back pain: An umbrella review

BACKGROUND

Numerous systematic reviews have attempted to synthesize evidence on prognostic factors for predicting future outcomes such as pain, disability and return-to-work/work absence in neck and low back pain populations.

DATABASES AND DATATREATMENT

An umbrella review of systematic reviews was conducted to summarize the magnitude and quality of the evidence for each prognostic factor investigated. Searches were limited to the last 10 years (2008-11th April 2018, updated 28th September 2020). A two-stage approach was undertaken: in stage one, data on prognostic factors was extracted from systematic reviews identified from the systematic search that met the inclusion criteria. Where a prognostic factor was investigated in ≥1 systematic review and where 50% or more of those reviews found an association between the prognostic factor and one of the outcomes of interest, it was taken forward to stage two. In stage two, additional information extracted included the strength of association found, consistency of effects and risk of bias. The GRADE approach was used to grade confidence in the evidence.

RESULTS

Stage one identified 41 reviews (90 prognostic factors), with 35 reviews (25 prognostic factors) taken forward to stage two. Seven prognostic factors (disability/activity limitation, mental health; pain intensity; pain severity; coping; expectation of outcome/recovery and fear-avoidance) were judged as having moderate confidence for robust findings.

CONCLUSIONS

Although there was conflicting evidence for the strength of association with outcome, these factors may be used for identifying vulnerable subgroups or people able to self-manage. Further research can investigate the impact of using such prognostic information on treatment/referral decisions and patient outcomes.

Measurement Properties of the Sedentary Behavior Questionnaire in Patients with Chronic Nonspecific Low Back Pain

BACKGROUND

The Sedentary Behavior Questionnaire (SBQ) is a brief and easy instrument to measure time spent on sedentary activities; however, no study has investigated the reliability and validity of this questionnaire in people with chronic low back pain (LBP).

OBJECTIVE

To investigate the internal consistency, test-retest reliability, measurement error, construct validity, and interpretability of the SBQ against data derived from an accelerometer in patients with nonspecific chronic LBP.

STUDY DESIGN

Cross-sectional study.

SETTING

Outpatient physiotherapy clinic.

PATIENTS

Seventy-five patients aged between 18 and 60 years (mean age, 42 years old) with nonspecific chronic LBP were recruited for this study.

INTERVENTIONS

Not applicable.

METHODS

The Cronbach's α was calculated to investigate the internal consistency of the SBQ and the intraclass correlation coefficient (ICC) was calculated to investigate the reliability of the SBQ between two administrations separated by a 1-week interval. Measurement error was assessed calculating the SEM and minimal detectable change (MDC). Spearman correlation (r) was calculated to investigate the construct validity using hypothesis testing. Interpretability was investigated using ceiling and floor effects.

RESULTS

The Cronbach's α of the SBQ total score was 0.92, indicating homogeneity among the items of the instrument. The reliability of the SBQ was excellent (ICC > 0.75), without any evidence of ceiling and floor effects. Regarding measurement error, the total score of the SBQ showed an SEM and MDC of 109.8 minutes per day and 304.4 minutes per day, respectively. However, there were no correlations of the SBQ domains or the total score with the accelerometer-measured sedentary time (r < 0.25).

CONCLUSION

The SBQ is a reliable tool for quantifying time spent in sedentary activities of patients with chronic LBP. The SBQ showed poor construct validity compared to the accelerometer-measured sedentary time, which indicates that patients may underestimate their time spent in sedentary activities.

Predictors of low back disability in chiropractic and physical therapy settings

Background

Predicting ongoing disability for chronic non-specific low back pain (LBP) is important to avoid prolonged disability.

Objective

Determine predictors of disability at 6 month follow-up in patients with LBP at medium risk of ongoing disability.

Methods

Baseline data was collected from 108 patients with medium-risk chronic non-specific LBP (mean age 50.4 years, SD 13.6) from six private chiropractic and physiotherapy clinics in Australia who took part in a randomised control trial. All patients received a pragmatic course of multimodal physical treatments [e.g., manual therapy (spinal manipulation or mobilization and/or soft tissue massage)] combined with advice, education and exercise. Baseline prognostic variables included sociodemographic, physical and psychological characteristics. Primary outcome was disability (Roland Morris Disability) at 6 month follow-up. Multivariable linear regression analysis was conducted.

Results

Variables remaining in the final multivariable model: lower work ability (β = − 1.05, 95% CI − 1.40 to − 0.70; p < 0.0001) and consultation with a medical specialist for back pain in the preceding 3 months (β = 3.35, 95% CI 1.14 to 5.55; p < 0.003), which significantly predicted higher disability at 6 months (unadjusted R ² = 0.31). Those with a lower work ability (scale 1 to 10) and who had seen a medical specialist for their back pain were more likely to report greater LBP-related disability at 6 months.

Conclusion

Patients with chronic LBP presenting to primary care with lower work ability and recent consultation with a medical specialist for LBP are more likely to have a worse prognosis; these are indicators to clinicians that standard conservative care may not adequately manage the patients’ needs.

Association between objectively measured physical behaviour and neck- and/or low back pain: A systematic review

BACKGROUND AND OBJECTIVE

Clinical guidelines recommend physical activity to manage neck pain (NP) and low back pain (LBP). However, studies used to support these guidelines are based on self-reports of physical behaviour, which are prone to bias and misclassification. This systematic review aimed to investigate associations between objectively measured physical behaviour and the risk or prognosis of NP and/or LBP.

DATABASES AND DATA TREATMENT

Literature searches were performed in MEDLINE, Embase and Scopus from their inception until 18 January 2019. We considered prospective cohort studies for eligibility. Article selection, data extraction and critical appraisal were carried out by independent reviewers. Results were stratified on activity/sedentariness.

RESULTS

Ten articles out of 897 unique records identified met the inclusion criteria, of which eight studied working populations with mainly blue-collar workers. The overall results indicate that increased sitting time at work reduces the risk of NP and LBP while increased physical activity during work and/or leisure increases the risk of these conditions among blue-collar workers; however, associations were weak. Physical activity was not associated with prognosis of LBP (no studies investigated prognosis of NP). Most of the included articles have methodological shortcomings.

CONCLUSIONS

This review indicates that, among blue-collar workers, increased sitting at work may protect against NP and LBP while increased physical activity during work and/or leisure may increase this risk. There was no evidence supporting physical activity as a prognostic factor for LBP. Findings should be interpreted with caution due to the weak associations and few available studies with methodological shortcomings.

SIGNIFICANCE

Based on prospective cohort studies with objectively measured physical behaviour, this review questions the common notion that increased physical activity is associated with reduced risk or better prognosis of NP and/or LBP. We found that, among blue-collar workers, increased sitting time at work reduces the risk of NP and LBP, whereas physical activity somewhat increases the risk. Despite methodological shortcomings, there was consistency in the direction of the results, although high-quality articles reported the weakest associations. Systematic review registration: PROSPERO CRD42018100765.