# Effectiveness of Transcutaneous Spinal Cord Stimulation for Lower Limb Rehabilitation in Spinal Cord Injury: Protocol for a Systematic Review and Meta-Analysis

## TL;DR

This study will evaluate how well transcutaneous spinal cord stimulation helps improve lower limb function in people with spinal cord injuries.

## Contribution

This is the first systematic review and meta-analysis specifically evaluating the effectiveness of tSCS for lower limb rehabilitation in SCI.

## Key findings

- The study will assess lower limb motor function, walking ability, spasticity, and quality of life outcomes.
- It will synthesize evidence from RCTs and nonrandomized studies using PRISMA and Cochrane guidelines.
- Results will inform clinical guidelines and future research on tSCS for SCI rehabilitation.

## Abstract

Spinal cord injury (SCI) affects millions of people worldwide and often results in impaired lower limb function and reduced mobility. Transcutaneous spinal cord stimulation (tSCS) has emerged as a promising neuromodulation technique for enhancing motor recovery and walking ability in individuals with SCI.

This systematic review and meta-analysis will determine the effectiveness of tSCS, compared with sham stimulation, no intervention, or other active interventions, for improving lower limb motor function in individuals with SCI. Secondary objectives are to evaluate tSCS effects on walking ability, spasticity, quality of life, and safety outcomes.

This systematic review will be conducted according to the Cochrane Handbook for Systematic Reviews of Interventions and reported following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 statement. We will search electronic databases (PubMed, Web of Science, Embase, CINAHL, MEDLINE, Cochrane Library, Physiotherapy Evidence Database, and Scopus) from inception to August 2025, along with gray literature, trial registries, and hand-searching of key journals. We will include randomized controlled trials (RCTs), quasi-RCTs, and nonrandomized studies (case series with ≥5 participants) that evaluate the effects of tSCS applied over the spinal region on lower limb rehabilitation outcomes in adults with traumatic or nontraumatic SCI. The primary outcome will be lower limb motor function assessed by validated measures such as the Lower Extremity Motor Score. Secondary outcomes will include walking ability, balance, functional independence, spasticity, quality of life, and adverse events. Two reviewers will independently screen studies, extract data, and assess risk of bias using version 2 of the Cochrane Risk of Bias tool for RCTs and Risk of Bias in Non-randomized Studies of Interventions tool. Data will be synthesized using random-effects meta-analysis if appropriate, with subgroup analyses examining injury level, completeness, stimulation site, and cointervention effects, and sensitivity analyses. Evidence certainty will be evaluated using the Grading of Recommendations Assessment, Development, and Evaluation approach.

This protocol paper presents strategy development and protocol registration, with results expected by October 2025.

This comprehensive systematic review and meta-analysis will address an important evidence gap, providing the first focused evaluation of tSCS effectiveness for lower limb rehabilitation in SCI. Results will inform clinical practice guidelines and guide future research directions.