Electromyographic Analyses of Trunk Musculature after Stroke: An Integrative Review

Background: Observational and intervention studies examining trunk electromyographic (EMG) activity following stroke are underpowered and fail criteria for systematic reviews of randomized control trials. Objective: To systematically evaluate and summarize evidence about trunk muscle activation after stroke during ADL and with diagnostic and therapeutic interventions. Methods: Search databases were Medline Complete, CINAHL and Health Sources: Nursing Academic Edition. Studies written in English after 1989 included these search terms: stroke, muscle activity, and trunk including abdominal or back muscles. Systematic reviews, single case studies, dissertations, or letters to the editor were excluded. Reviewers used Covidence to screen relevant research and extract information after title, abstract, and full-text screening. Information extracted related to stroke severity, time since onset, specific muscles and EMG analysis technique, and study limitations. Articles were classified as observational, intervention or device-related. Results: The electronic search yielded 188 articles and a hand search found 3. Title and abstract screening yielded 102 articles for full text screening. Ultimately, 45 articles were extracted. Trunk muscle recruitment during function and movement demonstrated significant differences in trunk EMG recruitment timing, magnitude, and symmetry after stroke when compared with healthy participants. Individuals with stroke demonstrated significant differences when comparing paretic to non-paretic side trunk EMG measures. Intervention studies showed some effect on improving trunk muscle activation but they had small sample sizes and methodological issues. Conclusions: Trunk muscle activation after stroke can be monitored with EMG during rehabilitation programs which challenge functional recovery.