Neuromuscular Electrical Stimulation Improves Activities of Daily Living Post Stroke: A Systematic Review and Meta-analysis

OBJECTIVES: (1) To elucidate the effectiveness of neuromuscular electrical stimulation (NMES) toward improving activities of daily living (ADL) and functional motor ability post stroke and (2) to investigate the influence of paresis severity and the timing of treatment initiation for the effectiveness of NMES. DATA SOURCES: PubMed, MEDLINE, Embase, Physiotherapy Evidence Database (PEDro) and Cochrane Library searched for relevant articles from database inception to May 2020. STUDY SELECTION: The inclusion criteria were randomized controlled trials exploring the effect of NMES toward improving ADL or functional motor ability in survivors of stroke. The search identified 6064 potential articles with 20 being included. DATA EXTRACTION: Two independent reviewers conducted the data extraction. Methodological quality was assessed using the PEDro scale and the Cochrane Risk of Bias Tool. DATA SYNTHESIS: Data from 428 and 659 participants (mean age, 62.4 years; 54% male) for outcomes of ADL and functional motor ability, respectively, were pooled in a random-effect meta-analysis. The analysis revealed a significant positive effect of NMES toward ADL (standardized mean difference [SMD], 0.41; 95% CI, 0.14-0.67; P=.003), whereas no effect on functional motor ability was evident. Subgroup analyses showed that application of NMES in the subacute stage (SMD, 0.44; 95% CI, 0.09-0.78; P=.01) and in the upper extremity (SMD, 0.34; 95% CI, 0.04-0.64; P=.02) improved ADL, whereas a beneficial effect was observed for functional motor abilities in patients with severe paresis (SMD, 0.41; 95% CI, 0.12-0.70; P=.005). CONCLUSIONS: The results of the present meta-analysis are indicative of potential beneficial effects of NMES toward improving ADL post stroke, whereas the potential for improving functional motor ability appears less clear. Furthermore, subgroup analyses indicated that NMES application in the subacute stage and targeted at the upper extremity is efficacious for ADL rehabilitation and that functional motor abilities can be positively affected in patients with severe paresis.