Exercise-Induced Hypoalgesia in people with chronic low back pain

Chronic low back pain (CLBP) is one of the most prevalent musculoskeletal disorders and a major contributor to disability worldwide. Exercise is recommended in guidelines as a cornerstone of the management of CLBP. One of the manifold benefits of exercise is its influence on endogenous pain modulation. An acute bout of exercise elicits a temporary decrease in pain sensitivity, described as exercise-induced hypoalgesia (EIH). This thesis explores EIH in people with CLBP via a systematic review and observational studies. The systematic review included 17 studies in people with spinal pain. Of those, four studies considered people with CLBP revealing very low quality evidence with conflicting results. EIH was elicited following remote cycling tasks (two studies, fair risk of bias), but EIH was altered following local repetitive lifting tasks (two studies, good/fair risk of bias). The observational studies investigated EIH following three different tasks in participants with and without CLBP and explored the stability of EIH results. Conflicting results from quantitative sensory testing were found for whether EIH is impaired in people with CLBP. EIH was only elicited in asymptomatic participants following a repeated lifting task, but both participants with and without CLBP showed EIH following a lumbar resistance and a brisk walking task. This thesis demonstrates the first evidence of stability of EIH over multiple sessions. However, the interpretation of the results can be challenging as stability was poor and changes in lumbar pressure pain thresholds also occurred after rest only. These findings are important to inform future studies contributing to the elucidation of the complex phenomenon of EIH in people with/without CLBP, specifically as the stability is a prerequisite for future research

People With Low Back Pain Display a Different Distribution of Erector Spinae Activity During a Singular Mono-Planar Lifting Task

This study aimed to investigate the variation in muscle activity and movement in the lumbar and lumbothoracic region during a singular mono-planar lifting task, and how this is altered in individuals experiencing low back pain (LBP). Muscle activity from the lumbar and lumbothoracic erector spinae of 14 control and 11 LBP participants was recorded using four 13 × 5 high-density surface electromyography (HDEMG) grids. Root mean squared HDEMG signals were used to create spatial maps of the distribution of muscle activity. Three-dimensional kinematic data were recorded focusing on the relationship between lumbar and thoracic movements. In the task, participants lifted a 5 kg box from knee height to sternal height, and then returned the box to the starting position. The center of muscle activity for LBP participants was found to be systematically more cranial throughout the task compared to the control participants (P 0.05). These results indicate that participants with LBP utilize an altered motor control strategy to complete a singular lifting task which is not reflected in their movement strategy. While no differences were identified between groups in the motion between lumbar and thoracic motion segments, participants with LBP utilized a less homogenous, less diffuse and more cranially focussed contraction of their erector spinae to complete the lifting movement. These results may have relevance for the persistence of LBP symptoms and the development of new treatments focussing on muscle retraining in LBP

Lack of exercise-induced hypoalgesia to repetitive back movement in people with chronic low back pain

© 2019 World Institute of Pain Purpose: To investigate whether people with chronic low back pain (LBP) show dysfunctional exercise-induced hypoalgesia (EIH) in response to repeated contractions of their back muscles during a lifting task. Methods: In this cross-sectional observational study conducted on asymptomatic participants (n = 18) and participants with chronic LBP (n = 21), quantitative sensory testing (QST) was applied extensively over the lumbar region and a remote area before and after a repeated task that involved lifting a 5-kg box for ~7 minutes. QST included pressure pain thresholds (PPTs), thermal detection, pain thresholds, and measures of temporal summation. Topographical maps of the percentage change in PPT detected at 16 locations over the lumbar region were generated to explore regional differences and compared between groups. Results: Mean (standard deviation) PPTs measured from 16 sites over the lower back changed significantly in asymptomatic participants (+29.78 kPa [41.4]) following task completion, indicative of EIH, whereas no significant change was observed for the low back pain (LBP) group (−14.87 kPa [61.2]). No changes were detected at the remote site for either group. No changes were revealed for the thermal tests. Temporal summation data revealed decreasing pain sensitivity as the test progressed, but the test response did not change after the exercise for either group. Conclusion(s): Unlike asymptomatic individuals, participants with LBP lacked EIH over the lumbar erector spinae muscles following repeated lifting. Although these results should be considered in relation to the study limitations, particularly the absence of a control group, the findings support impaired EIH in patients with LBP

Physiotherapists’ views of implementing a stratified treatment approach for patients with low back pain in Germany: a qualitative study

Abstract Background The STarT-Back-Approach (STarT: Subgroups for Targeted Treatment) was developed in the UK and has demonstrated clinical and cost effectiveness. Based on the results of a brief questionnaire, patients with low back pain are stratified into three treatment groups. Since the organisation of physiotherapy differs between Germany and the UK, the aim of this study is to explore German physiotherapists’ views and perceptions about implementing the STarT-Back-Approach. Methods Three two-hour think-tank workshops with physiotherapists were conducted. Focus groups, using a semi-structured interview guideline, followed a presentation of the STarT-Back-Approach, with discussions audio recorded, transcribed and qualitatively analysed using content analysis. Results Nineteen physiotherapists participated (15 female, mean age 41.2 (SD 8.6) years). Three main themes emerged, each with multiple subthemes: 1) the intervention (15 subthemes), 2) the healthcare context (26 subthemes) and 3) individual characteristics (8 subthemes). Therapists’ perceptions of the extent to which the STarT-Back intervention would require changes to their normal clinical practice varied considerably. They felt that within their current healthcare context, there were significant financial disincentives that would discourage German physiotherapists from providing the STarT-Back treatment pathways, such as the early discharge of low-risk patients with supported self-management materials. They also discussed the need for appropriate standardised graduate and post-graduate skills training for German physiotherapists to treat high-risk patients with a combined physical and psychological approach (e.g., communication skills). Conclusions Whilst many German physiotherapists are positive about the STarT-Back-Approach, there are a number of substantial barriers to implementing the matched treatment pathways in Germany. These include financial disincentives within the healthcare system to early discharge of low-risk patients. Therapists also highlighted the need for solutions in respect of scalable physiotherapy training to gain skills in combined physical and psychological approaches

Additional File 1:

Interview Guideline. (PDF 75 kb

Additional File 2:

Subthemes. (PDF 190 kb