Does non-invasive brain stimulation improve spatiotemporal gait parameters in people with multiple sclerosis? A systematic review and meta-analysis

Background: Multiple sclerosis (MS) is a chronic autoimmune disease that causes progressive functional impairment, mainly in walking tasks. Noninvasive brain stimulation (NIBS) could influence the motor function and improving gait ability of patients. Objective: The aim was to analyze the effects of NIBS (transcranial direct current stimulation [tDCS] or transcranial magnetic stimulation [TMS] on functional locomotion in people with multiple sclerosis (PwMS). Methods: A search was conducted for randomized controlled trials published up to November 2023 comparing the application of NIBS versus a sham or control group. The primary outcome were spatiotemporal gait parameters and functional mobility. Two review authors independently assessed the risk of bias in the included studies, and we used the Grading of Recommendations Assessment, Development, and Evaluation methodology to rate the certainty of the evidence for each outcome. A meta-analysis was performed by pooling the appropriate data using RevMan Web. Results: A total of four clinical trials were included for metanalysis. We observed that there is no statistically significant difference in overall effect in gait speed (MD = 0.08; 95% CI: - 0.08-0.24; p = 0.32), and cadence (MD = 0.22; 95% CI: - 11.54-11.98; p = 0.97%) between groups. But there was a statistically significant difference in overall effect in stride length between groups (MD:0.19; 95% CI: 0.07-0.31; p = 0.002), mainly when the intervention performed by multiple sessions and associated with motor rehabilitation (MD = 0.29; 95% CI: 0.14-0.44; p = 0.0002). Conclusions: tDCS applied by multiple session and combined with motor rehabilitation (i.e., aerobic and/or resistance training) can improve stride length in PwMS.