Transcranial Direct Current Stimulation Combined Neuromuscular Electrical Stimulation on Motor Recovery in Stroke

Background and objectives: Previous studies have shown that transcranial direct current stimulation (tDCS) and Neuromuscular electrical stimulation (NMES) could be effective for promoting motor recovery of stroke patients. However, the effects of tDCS combined with NMES on upper extremity (UE) motor recovery in patients with stroke have not been investigated. The purpose of this study was to investigate the effects of the combination treatment strategy. Methods: A randomized, double-blinded and sham-stimulation study was conducted. Twenty-six participants with chronic stroke (onset > 6 months) were assigned into one of three groups (tDCS combined with NMES, tDCS combined with sham NMES, or sham tDCS combined with sham NMES) by block randomization. In addition to conventional rehabilitation, all subjects received an additional protocol with a total of 15 sessions for 3 weeks (5 times per week, 30 minutes daily). The UE subscale of Fugl-Meyer assessment (UE-FMA) and Action Research Arm Test (ARAT) as primary outcome measures were assessed at beginning of the intervention, after 3-week of treatment, and one-month follow-up. Results: Most of the participants had mild to moderate disability in activity of daily living. No significant differences in the primary outcome measures at post-treatment and one-month follow-up were found among the tDCS combined with NMES group (n=9), tDCS combined with sham NMES group (n=9), and the sham tDCS combined with sham NMES group (n=8). However, significant changes in UE-FMA (from baseline to post-treatment, p= .02) and ARAT (from baseline to post-treatment, p= .04) score were found for the tDCS combined with NMES group. Conclusion: This preliminary study reveals that the tDCS combined with NMES appears to be beneficial to UE motor recovery after stroke but is not superior to the tDCS alone.