The effects of needling therapies on muscle force production: A systematic review and meta-analysis

BACKGROUND: Needling has been shown to decrease pain in the short term; however, its effects on muscle force production are unclear. OBJECTIVE: To evaluate the evidence regarding the comparative effects of needling on muscle force production. METHODS: In this systematic review, an electronic search was performed using key words related to needling. Methodological quality of articles was appraised and effect sizes were calculated. The strength of evidence was determined, and meta-analysis was performed when similar methods were used in studies for similar conditions. RESULTS: Twenty-one studies were included in this review, of which 9 were deemed to be of high quality (greater than 6/10 on the Physiotherapy Evidence Database [PEDro] scale), 11 of fair quality (5 to 6/10), and 1 of poor quality (less than 5/10). Three meta-analyses were performed. There was moderate strength of evidence and medium effect sizes for needling therapy to enhance force production in those with neck pain, and very low strength of evidence of no effect for individuals with nonspecific and postoperative shoulder pain and those with lateral epicondylalgia. Other studies not included in the 3 meta-analyses demonstrated no significant effect of needling on force production. These studies included individuals with carpal tunnel syndrome, knee osteoarthritis, ankle sprains, knee arthroscopy, or delayed-onset muscle soreness. CONCLUSION: The majority of studies suggest no effect of dry needling on force production. High-quality studies with adequate power that control for the placebo effect and follow accepted reporting standards could make valuable contributions to the literature.