The Effects of Stabilization Exercise on the Thickness of Lateral Abdominal Muscles During Standing Tasks in Women With Chronic Low Back Pain: A Randomized Triple-Blinded Clinical Trial Study

Home Exercise Programs Are Infrequently Prescribed in Trials of Supervised Exercise for Individuals With Low Back Pain: A Scoping Review of 292 Randomized Controlled Trials

OBJECTIVES: To (1) determine how often home exercise programs (HEPs) are prescribed in supervised exercise trials for low back pain (LBP) and (2) describe characteristics of the HEP programs (design, purpose, dose, and adherence). DESIGN: Scoping review. LITERATURE SEARCH: PubMed, CINAHL, and Ovid MEDLINE were searched from January 1, 2010, to August 17, 2021. STUDY SELECTION CRITERIA: Randomized controlled trials that included adults with LBP who received exercise interventions. DATA SYNTHESIS: The presence or absence of a prescribed HEP and any details of the HEP including design, dose, and adherence were extracted and summarized. RESULTS: Of 2689 potentially relevant trials, 292 were eligible for inclusion. Ninety-four trials (32%) included a HEP. The most commonly prescribed home exercises were core stability, trunk strengthening, and motor control exercises. There was great variation in the frequency and duration with which HEPs were prescribed. Adherence to HEPs was measured in fewer than half of the trials, and the methods for measuring adherence were inconsistent. Adherence to HEPs ranged from 29% to 82% in the 21 trials that reported adherence. CONCLUSION: Home exercise programs are not regularly prescribed in supervised exercise trials for LBP. There was considerable variation in prescribing HEPs and monitoring exercise adherence in trials of exercise-based treatments for adults with LBP. There is no consistent method used to measure participants' adherence to HEPs, and adherence percentages vary widely. J Orthop Sports Phys Ther 2023;53(3):120-142. Epub: 16 January 2023. doi:10.2519/jospt.2023.11448.

Effect of Motor Control Training on Trunk Muscle Morphometry, Pain, and Disability in People With Chronic Low Back Pain: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this systematic review and meta-analysis was to study the effects of motor control training (MCT) on trunk muscle morphometry measured by ultrasound imaging and pain and disability in individuals with chronic low back pain.

METHODS

PubMed, Web of Science, Scopus, and Cochrane Library databases were searched from study inception until January 2021. Randomized control trials evaluating both muscle morphometry and pain or disability in individuals with chronic low back pain were included. Study selection, data extraction, and quality assessment were performed by 2 reviewers independently. Modified Downs and Black tool and the Grading of Recommendations Assessment, Development and Evaluation approach were used to assess the risk of bias and quality of evidence, respectively. A meta-analysis was performed using a random effects model with mean difference or standardized mean difference (SMD).

RESULTS

Of 3459 studies initially identified, 15 studies were included, and 13 studies were selected for meta-analysis. The results revealed no differences in the resting thickness of the transversus abdominis, internal and external oblique, and lumbar multifidus muscles in studies that compared MCT with other interventions. The transversus abdominis muscles contraction ratio was greater (SMD = 0.93; 95% confidence interval [CI], -0.0 to 1.85) and lower pain (weighted mean difference: -1.07 cm; 95% CI, -1.91 to -0.22 cm; P = .01) and disability (SMD = -0.86; 95% CI, -1.42 to -0. 29; P < .01) scores were found in the groups who underwent MCT compared with other interventions.

CONCLUSION

This systematic review and meta-analysis found that motor control exercise training increased the transverse abdominis contraction ratio (muscle activation) and improved the level of pain and disability compared to other interventions in people with chronic low back pain. However, motor control exercise training was not superior to other interventions in increasing the resting thickness of deep abdominal and lumbar multifidus muscles in intervention times less than 12 weeks.

Exercise therapy for chronic low back pain

BACKGROUND

Low back pain has been the leading cause of disability globally for at least the past three decades and results in enormous direct healthcare and lost productivity costs.

OBJECTIVES

The primary objective of this systematic review is to assess the impact of exercise treatment on pain and functional limitations in adults with chronic non-specific low back pain compared to no treatment, usual care, placebo and other conservative treatments.

SEARCH METHODS

We searched CENTRAL (which includes the Cochrane Back and Neck trials register), MEDLINE, Embase, CINAHL, PsycINFO, PEDro, SPORTDiscus, and trials registries (ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform), and conducted citation searching of relevant systematic reviews to identify additional studies. The review includes data for trials identified in searches up to 27 April 2018. All eligible trials have been identified through searches to 7 December 2020, but have not yet been extracted; these trials will be integrated in the next update.

SELECTION CRITERIA

We included randomised controlled trials that assessed exercise treatment compared to no treatment, usual care, placebo or other conservative treatment on the outcomes of pain or functional limitations for a population of adult participants with chronic non-specific low back pain of more than 12 weeks' duration.

DATA COLLECTION AND ANALYSIS

Two authors screened and assessed studies independently, with consensus. We extracted outcome data using electronic databases; pain and functional limitations outcomes were re-scaled to 0 to 100 points for meta-analyses where 0 is no pain or functional limitations. We assessed risk of bias using the Cochrane risk of bias (RoB) tool and used GRADE to evaluate the overall certainty of the evidence. When required, we contacted study authors to obtain missing data. To interpret meta-analysis results, we considered a 15-point difference in pain and a 10-point difference in functional limitations outcomes to be clinically important for the primary comparison of exercise versus no treatment, usual care or placebo.

MAIN RESULTS

We included 249 trials of exercise treatment, including studies conducted in Europe (122 studies), Asia (38 studies), North America (33 studies), and the Middle East (24 studies). Sixty-one per cent of studies (151 trials) examined the effectiveness of two or more different types of exercise treatment, and 57% (142 trials) compared exercise treatment to a non-exercise comparison treatment. Study participants had a mean age of 43.7 years and, on average, 59% of study populations were female. Most of the trials were judged to be at risk of bias, including 79% at risk of performance bias due to difficulty blinding exercise treatments. We found moderate-certainty evidence that exercise treatment is more effective for treatment of chronic low back pain compared to no treatment, usual care or placebo comparisons for pain outcomes at earliest follow-up (MD -15.2, 95% CI -18.3 to -12.2), a clinically important difference. Certainty of evidence was downgraded mainly due to heterogeneity. For the same comparison, there was moderate-certainty evidence for functional limitations outcomes (MD -6.8 (95% CI -8.3 to -5.3); this finding did not meet our prespecified threshold for minimal clinically important difference. Certainty of evidence was downgraded mainly due to some evidence of publication bias.  Compared to all other investigated conservative treatments, exercise treatment was found to have improved pain (MD -9.1, 95% CI -12.6 to -5.6) and functional limitations outcomes (MD -4.1, 95% CI -6.0 to -2.2). These effects did not meet our prespecified threshold for clinically important difference. Subgroup analysis of pain outcomes suggested that exercise treatment is probably more effective than education alone (MD -12.2, 95% CI -19.4 to -5.0) or non-exercise physical therapy (MD -10.4, 95% CI -15.2 to -5.6), but with no differences observed for manual therapy (MD 1.0, 95% CI -3.1 to 5.1). In studies that reported adverse effects (86 studies), one or more adverse effects were reported in 37 of 112 exercise groups (33%) and 12 of 42 comparison groups (29%). Twelve included studies reported measuring adverse effects in a systematic way, with a median of 0.14 (IQR 0.01 to 0.57) per participant in the exercise groups (mostly minor harms, e.g. muscle soreness), and 0.12 (IQR 0.02 to 0.32) in comparison groups.

AUTHORS' CONCLUSIONS

We found moderate-certainty evidence that exercise is probably effective for treatment of chronic low back pain compared to no treatment, usual care or placebo for pain. The observed treatment effect for the exercise compared to no treatment, usual care or placebo comparisons is small for functional limitations, not meeting our threshold for minimal clinically important difference. We also found exercise to have improved pain (low-certainty evidence) and functional limitations outcomes (moderate-certainty evidence) compared to other conservative treatments; however, these effects were small and not clinically important when considering all comparisons together. Subgroup analysis suggested that exercise treatment is probably more effective than advice or education alone, or electrotherapy, but with no differences observed for manual therapy treatments.

Effects of spinal stabilization exercise with real-time ultrasound imaging biofeedback in individuals with chronic nonspecific low back pain: a pilot study

The use of real-time ultrasound imaging (RUSI) as biofeedback to enhance the performance of spinal stabilization exercise and recovery from low back pain has been a recent trend in musculoskeletal rehabilitation. The aim of this pilot study was to evaluate whether it would be feasible to conduct a randomized controlled trial investigating the effects of spinal stabilization exercise with RUSI biofeedback in individuals with chronic nonspecific low back pain. This was a single-group pretest-posttest quasi-experimental study. Ten consecutive patients with chronic nonspecific low back pain met the study criteria. They received spinal stabilization exercise with the RUSI biofeedback focusing on lumbar multifidus muscle activation. The intervention was provided twice weekly for 6 weeks. Outcome measures were lumbar multifidus muscle cross-sectional area, pain, disability and quality of life assessed at baseline and after intervention. A paired t-test was applied and effect size (Cohen d) was computed. The recruitment and retention rates were 75% and 83% respectively. No adverse events were reported during the study. Compared with the baseline, the participants demonstrated statistically significant improvement in lumbar multifidus muscle cross-sectional area (P<0.05, d=1.03), pain (P<0.001, d=2.56) and disability (P<0.05, d=1.43) with large effect size after the intervention. However, no statistically significant differences were observed for physical and mental health (P>0.05) after the intervention. It was concluded that spinal stabilization exercise with RUSI biofeedback is effective in improving lumbar multifidus muscle cross-sectional area, pain and disability in individuals with chronic nonspecific low back pain. The results demonstrated the feasibility of conducting a future, larger-scale powered randomized controlled trial to confirm these preliminary findings.