Transcutaneous Vagus Nerve Stimulation Combined with Rehabilitation Training in the Intervention of Upper Limb Movement Disorders After Stroke: A Systematic Review

INTRODUCTION: Stroke often leaves behind a wide range of functional impairments, of which limb movement disorders are more common. Approximately 85% of patients have varying degrees of upper limb motor impairment. In recent years, transcutaneous vagus nerve stimulation combined with rehabilitation training has been gradually used in the rehabilitation of upper limb motor dysfunction after stroke and appears to have some therapeutic benefits. PURPOSE: We conducted the systematic review to evaluate the efficacy and safety of transcutaneous vagus nerve stimulation combined with rehabilitation training in the rehabilitation of upper limb motor dysfunction after stroke. METHODS: Six databases, including PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure Database (CNKI), Wanfang Database, and China Science and Technology Journal Database (VIP), were searched for January 1, 2016 to January 30, 2022. Randomized controlled trials using TVNS combined with rehabilitation training to intervene in upper limb motor dysfunction after stroke were included, and meta-analysis was performed using Review Manager 5.4.1 software. RESULTS: Total of 101 participants from 4 studies were included in this systematic review. These studies were evaluated using the Cochrane Review’s Handbook 5.1 evaluation criteria and PEDro scores, and meta-analysis was performed on the collected data. The systematic review shows a significant effect of TVNS combined with rehabilitation training on the Upper Extremity Fugl-Meyer Score (MD=3.58, 95% CI [2.34, 4.82], P<0.00001, I2=0%), Function Independent Measure Score (MD=3.86, 95% CI [0.45, 7.27], P=0.03, I2=0%) and the Wolf Motor Function Test Score (MD=3.58, 95% CI [1.97, 5.18], P<0.0001, I2=0%). CONCLUSION: Based on UE-FM, FIM, and WMFT scores, TVNS combined with rehabilitation training showed some improvement in upper limb motor dysfunction in post-stroke patients, but its long-term effects, stimulation sites, stimulation parameters, combined mode with rehabilitation training, and adverse effects still need further observation. REGISTRATION: PROSPERO: CRD42022312453 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022312453).