Comparison of Continuous and Gait-synchronized Transcutaneous Electrical Nerve Stimulation During Gait Training in...

Post-stroke gait dysfunction may involve impaired integration of motor commands, somatosensory feedback, and phase-dependent peripheral sensory input during locomotion. Transcutaneous electrical nerve stimulation (TENS) combined with gait training may provide additional sensory input, but the relevance of different temporal stimulation profiles remains unclear.

To evaluate the feasibility, safety, and preliminary clinical signals of continuous and gait-synchronized TENS during gait training in individuals with chronic stroke.

Twenty-four participants with chronic stroke were randomized to continuous stimulation (CS), gait-synchronized stimulation (GS), or sham stimulation during standardized gait training. Participants received 12 intervention sessions over 4 weeks. CS delivered non-phase-specific stimulation, whereas GS delivered stimulation according to stance and swing phases. Outcomes were assessed at baseline, post-intervention, and 8-week follow-up. The primary longitudinal analysis was conducted in the modified intention-to-treat (mITT) population using baseline-adjusted linear mixed-effects models, with false discovery rate correction applied to group × time interaction p-values across estimable outcomes.

One participant withdrew before intervention without baseline assessment; therefore, 23 participants were included in the mITT analysis. Intervention adherence was high, with 99% of scheduled sessions completed, and no intervention-related adverse events were reported. Comfortable gait speed showed no significant group × time interaction. Maximal gait speed and Berg Balance Scale showed nominal group × time interaction effects before correction, but these did not remain significant after false discovery rate correction. No robust group × time interaction effects were observed after correction. Exploratory per-protocol analyses were unadjusted for baseline imbalance and were interpreted as supportive only.

Continuous and gait-synchronized TENS combined with standardized gait training were feasible and well tolerated in individuals with chronic stroke. The adjusted analysis did not provide robust evidence of differential clinical effects among stimulation-timing groups after correction for multiple outcome testing. Larger, adequately powered trials are needed to determine whether continuous or gait-synchronized TENS provides clinically meaningful benefits during post-stroke gait rehabilitation.

No: KCT0008481. Registered 17 May, 2023, https://cris.nih.go.kr/cris/search/detailSearch.do?seq=24719&search_page=L.