Noninvasive Brain Stimulation for Motor Dysfunction After Incomplete Spinal Cord Injury

Abstract

Objective We aimed to examine the effectiveness of noninvasive brain stimulation on motor dysfunction after incomplete spinal cord injury. Methods The PubMed, Embase, and Cochrane Library were searched from the inception dates to April 30, 2022. Randomized controlled trials comparing the effects of noninvasive brain stimulation and sham stimulation on motor dysfunction in patients with incomplete spinal cord injury were included. Two reviewers performed the data extraction and assessed study quality using Cochrane Collaboration’s Tool. The primary outcomes involved upper limb function, lower limb function, spasticity, and activities of daily living. They were analyzed using meta-analysis method and the results were reported as standardized mean difference with 95% confidence interval. Results Fourteen studies involving 225 patients were included. Noninvasive brain stimulation reduced spasticity at the end of intervention (standardized mean difference = −0.68, 95% confidence interval = −1.32 to −0.03, P = 0.04) and 1-wk follow-up (standardized mean difference = −0.82, 95% confidence interval = −1.48 to −0.16, P = 0.02), but no beneficial effect at 1-mo follow-up (standardized mean difference = −0.32, 95% confidence interval = −1.06 to 0.42, P = 0.39). In addition, noninvasive brain stimulation also increased lower limb muscle strength at 1-mo follow-up (standardized mean difference = 0.69, 95% confidence interval = 0.11 to 1.28, P = 0.02). Other main outcomes were similar between groups. Conclusions Noninvasive brain stimulation can reduce spasticity, and the favorable effect can sustain for 1 wk after intervention. In addition, noninvasive brain stimulation can increase lower limb muscle strength at 1-mo follow-up.