Can cerebellar noninvasive brain stimulation improve lower limb function in stroke? Evidence from meta-analyses based on ICF

Lower limb dysfunction following a stroke substantially hinders mobility and independence. Cerebellar noninvasive brain stimulation (NIBS) has exhibited potential in enhancing lower limb functionality post-stroke. Our study aims to evaluate the effects from both statistical and clinical significance based on the International Classification of Functioning, Disability, and Health (ICF). We systematically searched PubMed, Embase, Web of Science, and Cochrane Library. With meta-analyses and network meta-analyses conducted. Data extraction and analyses based on Cochrane Handbook and ICF. Fifteen studies (n = 579 patients) were enrolled. Cerebellar NIBS revealed statistically significant differences in “Activity” components, including the Berg Scale (MD = 4.37), Timed Up and Go Test (TUG; MD = 3.32), and Barthel index (BI; MD = 8.01). However, no significant differences were noted in “Body” Functions (FMA-LL; MD = 2.97), with high-dose intermittent theta-burst stimulation indicating a potentially large effect size (MD = 5.26 vs. 0.68). The post-hoc network meta-analysis showed no statistical difference between electrical and magnetic cerebellar NIBS in “Activity” components. As per the low-to-moderate level evidence, cerebellar NIBS demonstrated statistically significant improvements in the “Activity” components (Berg, TUG, and BI), albeit these improvements did not translate into clinically meaningful differences, except for BI. Cerebellar noninvasive brain stimulation (NIBS) is emerging as a potential intervention for lower limb motor recovery post-stroke.Low-to-moderate evidence supports that it appears to statistically improve balance (Berg scale), gait efficiency (Timed Up and Go Test), and functional independence (Barthel index; BI) scores, albeit its clinical efficacy remains limited based on the minimal clinically important difference, except for BI.Treatment parameters, particularly stimulation dosage, are likely to influence the functional outcomes.Despite the generally low certainty of evidence, cerebellar NIBS is still recommended for stroke patients as per the current findings toward further clarifying its clinical impact on lower limb function. Cerebellar noninvasive brain stimulation (NIBS) is emerging as a potential intervention for lower limb motor recovery post-stroke. Low-to-moderate evidence supports that it appears to statistically improve balance (Berg scale), gait efficiency (Timed Up and Go Test), and functional independence (Barthel index; BI) scores, albeit its clinical efficacy remains limited based on the minimal clinically important difference, except for BI. Treatment parameters, particularly stimulation dosage, are likely to influence the functional outcomes. Despite the generally low certainty of evidence, cerebellar NIBS is still recommended for stroke patients as per the current findings toward further clarifying its clinical impact on lower limb function.