Muscle energy technique for non-specific low-back pain. A Cochrane systematic review

BackgroundLow back pain (LBP) is responsible for considerable personal suffering due to pain and reduced function, as well as being a societal burden due to costs of health care and lost work productivity. Muscle energy technique (MET) is a manual therapy treatment technique used predominantly by osteopaths, physiotherapists and chiropractors which involves alternating periods of resisted muscle contractions and assisted stretching. It is unclear whether MET is effective in reducing pain and improving function in people with LBP.ObjectivesTo examine the effectiveness of MET in the treatment of people with non-specific LBP compared with control interventions, with particular emphasis on subjective pain and disability outcomes.MethodsEight electronic databases and two clinical trials registers were searched from inception to May and June 2014 together with reference checking and citation searching of relevant systematic reviews. Randomised controlled trials assessing the effect of MET on pain or disability in patients with non-specific LBP were included. Two authors independently assessed the risk of bias and extracted the data. Meta-analysis was performed where clinical homogeneity was sufficient. The quality of the evidence for each comparison was assessed with the GRADE approach.ResultsThere were 12 randomized controlled trials with 14 comparisons included in the review, with a total sample of 500 participants across all comparisons. Included studies were typically very small (n = 20–72), all except one were assessed as being at high risk of bias, and all reported short-term outcomes. For the purposes of pooling, studies were divided into seven clinically homogenous comparisons according to the patient population (acute or chronic LBP) and the nature of the control intervention. The meta-analyses and GRADE assessment provided low-quality evidence that MET provided no additional benefit when either compared to, or added to, other therapies on the outcomes of pain and disability in the short-term.ConclusionThe quality of research related to testing the effectiveness of MET for treatment of people with LBP is poor. Studies were generally small and at high risk of bias due to methodological deficiencies. Studies conducted to date generally provide low-quality evidence that MET is not effective for patients with LBP. There is insufficient evidence to determine whether MET is likely to be effective in practice. Large, methodologically-sound studies are necessary to investigate the effectiveness of MET as an intervention for treatment of people with LBP.