Impact of acupuncture on muscle electromyography poststroke: A narrative review

We reviewed the effects of acupuncture on muscle electrophysiology in stroke patients, with an emphasis on the factors influencing these effects and the underlying mechanisms. A comprehensive search of Chinese and English literature was conducted using databases including China National Knowledge Infrastructure, PubMed, and Web of Science. The search covered studies published between 1990 and 2023, using MeSH terms and keywords such as "electromyography," "acupuncture," "stroke," and "mechanisms." After excluding duplicates, irrelevant articles, phase I clinical trials, meta-analyses, reviews, case reports, and case series, 32 original studies and clinical trials with well-defined methodologies and results were selected from an initial pool of 1587 publications. Snowballing techniques were also used to identify additional relevant literature. Acupuncture was found to exert a bidirectional regulatory effect on electromyographic activity, enhancing or inhibiting it depending on variables such as stimulation method, frequency, duration, timing, and acupoint selection. The variability of outcomes highlights the complexity of electromyographic modulation, which likely involves integrated physiological responses including neural pathways, neurotransmitters, related proteins, receptors, and other biomolecules. Future research should focus on elucidating these mechanisms to optimize the application of acupuncture in poststroke rehabilitation.