Transcutaneous spinal cord stimulation for stroke rehabilitation: a scoping review

BACKGROUND: Transcutaneous spinal cord stimulation (tSCS) is an emerging noninvasive neuromodulation approach for rehabilitation in individuals with stroke. Studies have suggested benefits, but evidence remains fragmented and methodologically heterogeneous. OBJECTIVE: This scoping review maps and synthesizes current evidence on tSCS for stroke rehabilitation, focusing on study design, stimulation parameters, outcome measures, and reported effects. METHODS: Following PRISMA-ScR guidelines, we systematically searched five databases (PubMed, Embase, Web of Science, CINAHL, and Google Scholar) from inception to December 2025. Two independent reviewers screened titles and abstracts, with a third resolving discrepancies. We extracted data on participant characteristics, stimulation parameters, outcome measures, and findings. RESULTS: Thirteen studies met inclusion criteria, comprising five randomized and eight non-randomized designs, with sample sizes ranging from 2 to 21 participants. Most studies enrolled predominantly male individuals with chronic stroke. Four studies used multi-session protocols while nine single session protocols. Stimulation parameters varied widely amplitude (5-250 mA), frequency (15-100 Hz), carrier frequency (0-10 kHz), and pulse width (0.5-2 ms). Ten studies targeted lower-extremity function, two upper extremity functions, and one autonomic function. Multi-session trials pairing tSCS with task-specific training reported improvements in selected outcomes, though small sample sizes limit generalization. CONCLUSIONS: tSCS remains an exploratory adjunctive intervention in stroke rehabilitation. Future research should prioritize adequately powered controlled trials with standardized stimulation protocols, stratification by stroke severity and chronicity, and long-term follow-up to establish clinical efficacy and optimal implementation in stroke rehabilitation.