The effect of focused extracorporeal shock wave therapy on myofascial pain syndrome of trapezius: A systematic review and meta-analysis

BACKGROUND: Myofascial pain syndrome (MPS) is commonly seen in clinical settings and negatively influences a patient's daily life. Recently, the application of extracorporeal shock wave therapy (ESWT) has been utilized as one of the treatment methods for MPS. The aim of this systematic review and meta-analysis was to summarize the current evidence for the short-term effect of ESWT on MPS of trapezius. METHODS: PubMed, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials were searched from the database inception to March 2019. Two reviewers independently screened articles, evaluated methodological quality, and extracted data. The primary outcome was post-interventional pain intensity. RESULTS: Randomized controlled trials (RCTs) were conducted to determine whether ESWT was used as the main treatment on MPS. The 5 studies reviewed in this meta-analysis were evaluated for changes in pain intensity. Compared with other treatments, focused ESWT in MPS was more effective in reducing the scores of visual analog scale (VAS) (standardized mean difference [SMD] = −0.48, 95% CI −0.74 to −0.22). CONCLUSIONS: There is very low level evidence that focused ESWT is effective for short-term relief of neck pain in MPS. The limited sample size and poor quality of these studies highlight and support the need for large scale, good quality placebo controlled trials in this area.