Abstract
PURPOSE: Chronic ankle instability (CAI) is related to sensorimotor dysfunction and maladaptive neuroplasticity. Transcranial direct current stimulation (tDCS) is considered a potential method for CAI rehabilitation, but its efficacy and underlying mechanisms remain inconclusive. This study aimed to comprehensively synthesise the current evidence of tDCS for sensorimotor recovery in CAI and evaluate its efficacy, moderating factors and potential mechanisms. METHODS: PubMed, Web of Science, Embase, SPORTDiscus and Scopus were searched in January 2026. The random effects model was employed to meta-analyses to estimate pooled effect sizes. Subgroup analyses and meta-regressions were performed to reveal potential moderators. Risk of bias was evaluated using the RoB 2 tool, and methodological quality was assessed using the PEDro scale. RESULTS: Eleven trials involving 310 participants were included. Compared with control, tDCS significantly improved balance control (g = 0.27, p = 0.009) and sensorimotor functional performance (g = 0.16, p = 0.023), whereas no statistically significant change was observed in kinematics (g = 0.16, p = 0.081), neural excitability (g = − 0.07, p = 0.633) and patient-reported outcomes (g = 0.11, p = 0.558). Subgroup analyses showed that online stimulation, High-definition transcranial direct current stimulation (HD-tDCS) and the combination with foot core exercise (FCE) appeared to yield enhanced improvements in balance. CONCLUSIONS: tDCS is of great promise to improve balance control and sensorimotor function in CAI. Still the underlying neurophysiological mechanisms should be more explicitly characterized. Future studies are warranted to examine such benefits of interventions using tDCS for individuals suffering from CAI. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12984-026-01916-9.