Noninvasive brain stimulation for upper limb motor activity in children and young adults with cerebral palsy and pediatric stroke: a systematic review and meta-analysis.

BACKGROUND: Cerebral palsy (CP) and pediatric stroke (PS) are nonprogressive neurological conditions, representing the leading cause of death and disability in children. Survivors commonly present impaired upper limb motor function, which significantly impacts their activities of daily living. Noninvasive brain stimulation (NIBS) techniques, such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), have shown promise for enhancing motor function by modulating cortical excitability. Despite their potential, the evidence supporting their effectiveness in improving upper limb motor activity in children with CP and PS remains inconclusive. METHODS: This systematic review and meta-analysis aimed to assess the efficacy of NIBS on upper limb activity in children and young adults with CP and PS. A comprehensive search was conducted across MEDLINE, SPORTDiscuss, CINAHL, CENTRAL and Web of Science databases to identify randomized controlled trials (RCTs). Eligible studies were assessed using the PEDro scale for methodological quality, and the risk of bias was evaluated with the Cochrane Risk of Bias tool. Data were synthesized using meta-analytic techniques, with subgroup analyses performed to explore heterogeneity. RESULTS: Twelve RCTs involving 291 participants met the inclusion criteria. Five studies evaluated rTMS, while seven focused on tDCS. The meta-analysis revealed no statistically significant improvements in upper limb motor activity for rTMS (SMD = 0.2218; p = 0.302) or tDCS (SMD = 0.345; p = 0.322). Notably, tDCS studies exhibited substantial heterogeneity (I2 = 71.23%; p = 0.005), likely due to differences in electrode montage, stimulation intensity, and session frequency. rTMS studies, in contrast, showed low heterogeneity. Despite these findings, exploratory analyses highlighted potential benefits when NIBS was combined with other interventions, such as constraint-induced movement therapy, suggesting synergistic effects on upper limb motor activity. CONCLUSIONS: While NIBS techniques alone did not significantly enhance upper limb motor activity in children with CP or PS, they hold potential as adjuncts to established rehabilitation strategies. Future research should focus on standardizing NIBS protocols, identifying optimal cortical targets, and evaluating the long-term impacts of combined therapeutic approaches. These efforts are critical to fully realizing the potential of NIBS in pediatric neurorehabilitation and improving outcomes for children with neurological motor impairments.