Effectiveness of muscle energy technique on the range of motion, flexibility, and function in musculoskeletal disorders: Systematic review and meta-analysis

OBJECTIVES: Muscle energy technique (MET) is a voluntary contraction of a patient's muscle in a predetermined direction, at varying levels of intensity. Its commonly used as a treatment option in musculoskeletal rehabilitation. This study aims to investigate the effectiveness of MET in the treatment of people with musculoskeletal injuries with particular emphasis on flexibility, range of motion (ROM), and function. METHODS: Scopus (via Science Direct), CINAHLvia (EBSCO), Embase (via OvidSP), PubMed, and PEDro were searched using specified keywords to select randomized controlled trials that assessed the effect of MET on flexibility, ROM, or function in patients with musculoskeletal disorders. Two authors extracted all related information from the included trials and presented them in an excel spreadsheet. Two other authors independently conducted the quality assessment. Meta-analysis was performed where homogeneity (similirty regarding population and outcomes) was sufficient and required data were available. RESULTS: A total of 42 studies were included. Yet, twelve joined the meta-analysis where six comparisons were conducted. Of them, four comparisons were composed of two trials, one comparison consisted of six, and another one was composed of four. No statistically significant differences were observed between MET and other comparators regarding function and ROM, especially in patients with low back or neck pain. MET was statistically significantly better than control or sham interventions on the flexibility of patients with sacroiliac joint (SIJ) problems. CONCLUSIONS: MET can produce better flexibility than placebo and control interventions in patients with SIJ problems. MET is not better than other interventions regarding function and ROM. Although the existence of multiple trials testing the effectiveness of MET, there is obvious heterogeneity. There is no sufficient evidence to reliably determine the clinical effect of MET in practice.