Electromyogram-triggered neuromuscular stimulation and stroke motor recovery of arm/hand functions: a meta-analysis

Debate persists about the effectiveness of poststroke behavioral interventions for progress toward motor recovery. The current meta-analysis assessed the effect of electromyogram (EMG)-triggered neuromuscular stimulation on arm and hand functions. Computer searches of PubMed and Cochran databases, as well as hand searches of reference lists identified seven EMG-triggered neuromuscular stimulation studies. Outcome measures focused on arm and hand motor capability functions. In addition, the quality of each study was rated on three guidelines: randomization, double blind, and dropouts. After adjusting data for consistency in the arm/hand outcome measures and to avoid bias, five active stimulation studies were included in the analysis. Rehabilitation treatment in each study focused on wrist extension. The total number of individuals in the treatment groups was 47 whereas the control groups had 39 subjects. The meta-analysis revealed a significant overall mean effect size (delta=0.82, S.D.=0.59). A homogeneity test indicated that the pooled standardized effect sizes estimated the same treatment effect. A fail-safe test for null effect findings revealed that 15 studies were required to reduce the large effect (0.82) to a small effect (0.20). These improved wrist extension motor capabilities findings support EMG-triggered neuromuscular stimulation as an effective poststroke protocol.