The deconditioning paradigm for chronic low back pain unmasked?

Virtual immersive gaming to optimize recovery (VIGOR) in low back pain: A phase II randomized controlled trial

The virtual immersive gaming to optimize recovery (VIGOR) study is a randomized controlled trial of the effects of virtual reality games to encourage lumbar spine flexion among individuals with chronic low back pain and fear of movement. Whereas traditional graded activity or graded exposure therapies for chronic low back pain have high attrition and poor long-term efficacy, we believe that virtual reality games have distinct advantages that can enhance adherence and clinical outcomes. First, they are engaging and enjoyable activities that can distract from pain and fear of harm. In addition, because they gradually reinforce increases in lumbar spine flexion to achieve game objectives, continued engagement over time is expected to promote recovery through restoration of normal spinal motion. The study design includes two treatment groups which differ in the amount of lumbar flexion required to achieve the game objectives. All participants will play the games for nine weeks, and pre-treatment to 1-week post-treatment changes in pain and disability will serve as the co-primary clinical outcomes. In addition, changes in lumbar flexion and expectations of pain/harm will be examined as potential treatment outcome mediators. Maintenance of treatment outcomes will also be assessed for up to 48-weeks post-treatment. In brief, we hypothesize that the virtual reality games will reduce pain and disability by promoting spinal motion and allowing participants to develop an implicit understanding that they are capable of engaging in significant lumbar spine motion in their daily lives without a risk of injury to their back.

Physical Activity Interventions for Increasing Objectively Measured Physical Activity Levels in Patients With Chronic Musculoskeletal Pain: A Systematic Review

OBJECTIVE

To investigate whether physical activity interventions increase objectively measured physical activity levels of patients with chronic musculoskeletal pain (e.g., osteoarthritis, low back pain) compared to no/minimal intervention.

METHODS

We performed a systematic review with meta-analysis searching the Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, SportDiscus, and Physiotherapy Evidence Database (PEDro) databases, and the main clinical trials registries. Quasirandomized or randomized controlled trials investigating the effect of physical activity interventions on objectively measured physical activity levels (e.g., using accelerometers or pedometers) of patients with chronic musculoskeletal pain compared with no/minimal intervention were considered eligible. Analyses were conducted separately for short-term (≤3 months), intermediate (>3 months and <12 months), and long-term (≥12 months) followups. Pooled effects were calculated using the standardized mean difference (SMD), and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used in summary conclusions.

RESULTS

Eight published trials and 6 registered trials were included. For the short-term followup, pooling of 6 trials showed no significant effect (SMD 0.34, 95% confidence interval -0.09, 0.77) between a physical activity intervention and no/minimal intervention. Similarly nonsignificant results were found for the intermediate and long-term followups. The overall evidence according to the GRADE approach was classified as low quality.

CONCLUSION

Our findings suggest that physical activity-based interventions may lead to little or no difference in objectively measured physical activity levels of patients with chronic musculoskeletal pain compared with no/minimal interventions. Given the number of registered trials, the pooled effect found in this review is likely to change once the results of these trials become available.

Associations between Trunk Extension Endurance and Isolated Lumbar Extension Strength in Both Asymptomatic Participants and Those with Chronic Low Back Pain

BACKGROUND

Strength and endurance tests are important for both clinical practice and research due to the key role they play in musculoskeletal function. In particular, deconditioning of the lumbar extensor musculature has been associated with low back pain (LBP). Due to the relationship between strength and absolute endurance, it is possible that trunk extension (TEX) endurance tests could provide a proxy measure of isolated lumbar extension (ILEX) strength and thus represent a simple, practical alternative to ILEX measurements. Though, the comparability of TEX endurance and ILEX strength is presently unclear and so the aim of the present study was to examine this relationship.

METHODS

Thirty eight healthy participants and nineteen participants with non-specific chronic LBP and no previous lumbar surgery participated in this cross-sectional study design. TEX endurance was measured using the Biering-Sorensen test. A maximal ILEX strength test was performed on the MedX lumbar-extension machine.

RESULTS

A Pearson's correlation revealed no relationship between TEX endurance and ILEX strength in the combined group (r = 0.035, p = 0.793), the chronic LBP group (r = 0.120, p = 0.623) or the asymptomatic group (r = -0.060, p = 0.720).

CONCLUSIONS

The results suggest that TEX is not a good indicator of ILEX and cannot be used to infer results regarding ILEX strength. However, a combination of TEX and ILEX interpreted together likely offers the greatest and most comprehensive information regarding lumbo-pelvic function during extension.

Does a patient's physical activity predict recovery from an episode of acute low back pain? A prospective cohort study

Background

Advice to remain active and normalisation of activity are commonly prescribed in the management of low back pain (LBP). However, no research has assessed whether objective measurements of physical activity predict outcome and recovery in acute low back pain.

Method

The aims of this study were to assess the predictive relationship between activity and disability at 3 months in a sub-acute LBP population. This prospective cohort study recruited 101 consenting patients with sub-acute LBP (< 6 weeks) who completed the Roland Morris Disability Questionnaire (RMDQ), the Visual Analogue Scale, and resumption of full ‘normal’ activity question (Y/N), at baseline and 3 months. Physical activity was measured for 7 days at both baseline and at 3 months with an RT3 accelerometer and a recall questionnaire.

Results

Observed and self-reported measures of physical activity at baseline and change in activity from baseline to 3 months were not independent predictors of RMDQ (p > 0.05) or RMDQ change (p > 0.05) over 3 months. A self-report of a return to full ‘normal’ activities was significantly associated with greater RMDQ change score at 3 months (p < 0.001). Paired t-tests found no significant change in activity levels measured with the RT3 (p = 0.57) or the recall questionnaire (p = 0.38) from baseline to 3 months.

Conclusions

These results question the predictive role of physical activity in LBP recovery, and the assumption that activity levels change as LBP symptoms resolve. The importance of a patient’s perception of activity limitation in recovery from acute LBP was also highlighted.

Trial registration

Clinical Trial Registration Number, ACTRN12609000282280

Pathoanatomy and classification of low back disorders

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

The relationship between physical activity and low back pain outcomes: a systematic review of observational studies

Although clinical guidelines advocate exercise and activity in the management of non-specific low back pain (NSLBP), the link between levels of physical activity and outcomes is unclear. This systematic review investigated the relationships between free living activity levels after onset of low back pain (LBP) and measures of pain, and disability in patients with NSLBP. Cohort and cross-sectional studies were located using OVID, CINAHL, Medline, AMED, Embase, Biomed, PubMed-National Library of Medicine, Proquest and Cochrane Databases, and hand searches of reference lists. Studies were included if a statistical relationship was investigated between measures of free living physical activity (PA) in subjects with LBP and LBP outcome measures. Twelve studies (seven cohort and five cross-sectional) were included. One prospective study reported a statistically significant relationship between increased leisure time activity and improved LBP outcomes, and one cross-sectional study found that lower levels of sporting activity were associated with higher levels of pain and disability. All other studies (n = 10) found no relationship between measures of activity levels and either pain or disability. Heterogeneity of study designs, particularly in terms of activity measurement, made comparisons between studies difficult. These data suggest that the activity levels of patients with NSLBP are neither associated with, nor predictive of, disability or pain levels. Validated activity measurement in prospective research is required to better evaluate the relationships between PA and LBP.

Comparison of graded exercise and graded exposure clinical outcomes for patients with chronic low back pain

STUDY DESIGN

Quasi-experimental clinical trial.

OBJECTIVES

This study compared outcomes from graded exercise and graded exposure activity prescriptions for patients participating in a multidisciplinary rehabilitation program for chronic low back pain. Our primary purpose was to investigate whether pain and disability outcomes differed based on treatment received (graded exercise or graded exposure). Our secondary purpose was to investigate if changes in selected psychological factors were associated with pain and disability outcomes.

BACKGROUND

Behavioral interventions have been advocated for decreasing pain and disability from low back pain, yet relatively few comparative studies have been reported in the literature.

METHODS

Consecutive sample with chronic low back pain recruited over a 16-month period from an outpatient chronic pain clinic. Patients received physical therapy supplemented with either graded exercise (n=15) or graded exposure (n=18) principles. Graded exercise included general therapeutic activities and was progressed with a quota-based system. Graded exposure included specific activities that were feared due to back pain and was progressed with a hierarchical exposure paradigm. Psychological measures were pain-related fear (Fear-Avoidance Beliefs Questionnaire, Tampa Scale for Kinesiophobia, Fear of Pain Questionnaire), pain catastrophizing (Coping Strategies Questionnaire), and depressive symptoms (Beck Depression Inventory). Primary outcome measures were pain intensity (visual analog scale) and self-report of disability (modified Oswestry Disability Questionnaire).

RESULTS

Statistically significant improvements (P<.01) were observed for pain intensity and disability at discharge. The rate of improvement did not differ based on behavioral intervention received (P>.05 for these comparisons). Overall, 50% of patients met criterion for minimally important change for pain intensity, while 30% met this criterion for disability. Change in depressive symptoms was associated with change in pain intensity, while change in pain catastrophizing was associated with change in disability.

CONCLUSIONS

Physical therapy supplemented with graded exercise or graded exposure resulted in equivalent clinical outcomes for pain intensity and disability. The overall treatment effects were modest in this setting. Instead of being associated with a specific behavioral intervention, reductions in pain and disability were associated with reductions in depressive symptoms and pain catastrophizing, respectively.

LEVEL OF EVIDENCE

Therapy, level 2b–.

The usability of a modified Astrand bicycle test to assess the aerobic capacity in patients with musculoskeletal pain and healthy controls

PURPOSE

The aim of this study was to assess the usability of a modified Astrand bicycle test in subjects with musculoskeletal pain disorder (MSPD) and healthy controls.

METHODS

In a random cross-over design, 31 subjects with a MSPD who have been referred to rehabilitation medicine and 33 healthy subjects matched for age, gender, height and body weight, performed an Astrand bicycle test and a modified test with a time interval of 7 days. Drop-out rates, VO2max values (in mL/kg lean body mass (LBM) min(-1)), intraclass correlation coefficients (ICCs) and critical difference (Bland-Altman plots) for both tests within each group of subjects were compared.

RESULTS

The drop-out rate in both tests for the MSPD group was comparable, and mainly caused by pain, fatigue or breathlessness. Compared with the modified version, the Astrand test showed higher VO2max-scores: 4.83 mL/kg LBM min(-1) (9.96%) in the MSPD group and 3.5 mL/kg LBM min(-1) (5.57%) in the healthy group. ICCs were 0.79 and 0.87 and the limits of agreement were 8.5 mL/kg LBM min(-1) (15.9%) and 10.2 mL/kg LBM min(-1) (18.1%), respectively.

CONCLUSION

The usability of the modified test is acceptable, as well as in healthy individuals as subjects suffering from MSPD being referred to rehabilitation medicine. However, a slight under estimation of VO2max with the modified test has to be taken into account.

Tender point count, pain, and mobility in the older population: the mobilize Boston study

Prevalence of tender points (TP), and widespread pain and fibromyalgia, as well as the relationship between TP and widespread pain and mobility, was examined in 585 community-dwelling older adults (mean age 78.2 years, 63.4% female). Pain was based on location (none, single site, multisite, widespread). Mobility was measured by the Short Physical Performance Battery (SPPB), gait speed, and self-reported (S-R) mobility difficulty. Tender-point count and health characteristics (ie, BMI, chronic conditions, analgesic use, number of medications, depression, and blocks walked per week) were assessed. Several participants had 3 or more TP (22.1%) although prevalence of criteria-based fibromyalgia was low (.3%). Mobility was more limited in persons with higher tender-point counts. After adjustment for pain and other risk factors, higher tender-point count was associated with poorer SPPB performance (score < 10, aOR = 1.09 per TP, 95%CI, 1.01-1.17), and slow gait speed (< .784m/sec, aOR = 1.14 per TP, 95%CI, 1.05-1.24), but not with S-R mobility difficulty. S-R mobility difficulty was associated with more disseminated pain (multisite pain, aOR = 2.01, 95%CI, 1.21-3.34; widespread pain, aOR = 2.47, 95%CI, 1.09-5.62). These findings portray a significant mobility burden related to tender-point count and multisite and widespread pain in the older population. Future studies using longitudinal methods are warranted.

PERSPECTIVE

Higher tender-point count, multisite pain, and widespread pain are common in community-dwelling older adults and associated with mobility problems. Both the manual tender-point exam and the McGill Pain Map may provide important yet different information about risks for mobility disability in older individuals.

Are fear-avoidance beliefs in low back pain patients a risk factor for low physical activity or vice versa? A cross-lagged panel analysis

Objective: The assumption that low back pain (LBP) patients suffer from “disuse” as a consequence of high fear-avoidance beliefs is currently under debate. A secondary analysis served to investigate whether fear-avoidance beliefs are associated cross-sectionally and longitudinally with the physical activity level (PAL) in LBP patients.

Methods: A total of 787 individuals (57% acute and 43% chronic LBP) were followed up over a period of one year with measurements of fear-avoidance beliefs and physical activity level. Fear-avoidance beliefs concerning physical activity were measured by the physical-activity subscale of the FABQ (Fear-Avoidance Beliefs Questionnaire), the physical activity level was assessed in weighted metabolic equivalents (MET) hours/week with a German self-report questionnaire. Data were investigated by structural equation modelling in a cross-lagged panel design for the whole sample and separately for acute and chronic LBP.

Results: The acute and chronic sub sample increased their total physical activity level significantly after one year. The structural equation modelling results did not support the disuse-aspect inherent in the fear-avoidance belief model. Cross-lagged path coefficients were low (.04 and .05 respectively) and, therefore, did not allow to predict final physical activity by initial fear-avoidance beliefs or vice versa.

Discussion: Consequently, due to missing links between fear-avoidance beliefs and physical activity in a longitudinal design, the assumptions of the fear-avoidance belief model have to be questioned. These findings are in line with other investigations published recently. Most probably, “fear-avoidance belief” represents a cognitive scheme that does not limit activity per se, but only is directed to the avoidance of specific movements.

A pilot study using Tissue Velocity Ultrasound Imaging (TVI) to assess muscle activity pattern in patients with chronic trapezius myalgia

Background

Different research techniques indicate alterations in muscle tissue and in neuromuscular control of aching muscles in patients with chronic localized pain. Ultrasound can be used for analysis of muscle tissue dynamics in clinical practice.

Aim

This study introduces a new muscle tissue sensitive ultrasound technique in order to provide a new methodology for providing a description of local muscle changes. This method is applied to investigate trapezius muscle tissue response – especially with respect to specific regional deformation and deformation rates – during concentric shoulder elevation in patients with chronic trapezius myalgia and healthy controls before and after pain provocation.

Methods

Patients with trapezius myalgia and healthy controls were analyzed using an ultrasound system equipped with tissue velocity imaging (TVI). The patients performed a standardized 3-cm concentric shoulder elevation before and after pain provocation/exercise at a standardized elevation tempo (30 bpm). A standardized region of interest (ROI), an ellipsis with a size that captures the upper and lower fascia of the trapezius muscle (4 cm width) at rest, was placed in the first frame of the loop registration of the elevation. The ROI was re-anchored frame by frame following the same anatomical landmark in the basal fascia during all frames of the concentric phase. In cardiac measurement, tissue velocities are measured in the axial projection towards and against the probe where red colour represents shortening and red lengthening. In the case of measuring the trapezius muscle, tissue deformation measurements are made orthogonally, thus, indirectly. Based on the assumption of muscle volume incompressibility, blue represents tissue contraction and red relaxation. Within the ROI, two variables were calculated as a function of time: deformation and deformation rate. Hereafter, max, mean, and quadratic mean values (RMS) of each variable were calculated and compared before and after pain provocation/exercise.

Results

This new methodology seems valuable when looking at local muscle changes and studying the mechanism behind chronic muscle pain. The univariate analyses indicate that patients with chronic trapezius myalgia after pain provocation due to exercise at group level showed decreased strain and unchanged strain rate while healthy controls had unchanged strain and increased strain rate. However, the multivariate analysis indicates that most patients showed lower levels according to both strain and strain rate after exercise compared to most controls.

Conclusion

Tissue velocity imaging can help describe musculoskeletal tissue activity and dynamics in patients with chronic pain conditions. An altered muscle tissue dynamic after pain provocation/exercise among the majority of trapezius myalgia patients compared with the healthy controls was found.

A randomized trial of behavioral physical therapy interventions for acute and sub-acute low back pain (NCT00373867)

Psychological factors consistent with fear-avoidance models are associated with the development of chronic low back pain (LBP). As a result, graded activity (GA) and graded exposure (GX) have been suggested as behavioral treatment options. This clinical trial compared the effectiveness of treatment-based classification (TBC) physical therapy alone to TBC augmented with GA or GX for patients with acute and sub-acute LBP. Our primary hypothesis was that GX would be most effective for those with elevated pain-related fear. In total, 108 patients enrolled in this clinical trial and were randomly assigned to receive TBC, GA, or GX. Outcomes were assessed by a blinded evaluator at 4 weeks and by mail at 6 months. The primary outcomes for this trial were disability and pain intensity, and the secondary outcomes were fear-avoidance beliefs, pain catastrophizing, and physical impairment. There were no differences in 4-week and 6-month outcomes for reduction of disability, pain intensity, pain catastrophizing, and physical impairment. GX and TBC were associated with larger reductions in fear-avoidance beliefs at 6 months only. Six-month reduction in disability was associated with reduction in pain intensity, while 6-month reduction in pain intensity was associated with reductions in fear-avoidance beliefs and pain catastrophizing. This trial suggests that supplementing TBC with GA or GX was not effective for improving important outcomes related to the development of chronic LBP.