The use of transcranial direct current stimulation in individuals with cerebral palsy: a scoping review

Abstract

BACKGROUND: Cerebral palsy (CP) is a neurodevelopmental condition that begins in early childhood and persists throughout life, causing limitations in daily activities and social participation. Neuromodulatory interventions using non-invasive brain stimulation, like transcranial direct current stimulation (tDCS), have been increasingly investigated, aiming to influence cortical excitability in neurologic conditions, including CP. OBJECTIVE: To summarize current evidence for the use of tDCS on individuals with CP. METHODS: Using scoping review methodology, the terms "cerebral palsy" and "transcranial direct current stimulation" were screened in PubMed, Cochrane, LILACS, SciELO, PEDro, and Embase databases, searching for clinical trials that applied tDCS interventions into children and adults with CP. Quality assessment of all eligible studies was performed using the PEDro Scale. RESULTS: A total of 1773 articles (including duplicates) were found, of which 14 met the predetermined criteria. Two hundred and thirty-three individuals with CP, with ages ranging from 5 to 27 years, participated in these studies. The main therapeutic effects of anodal tDCS were reported on upper limb dysfunctions, balance, and gait. The primary motor cortex was the most frequently applied target. The combined use of tDCS with other motor training techniques, such as constraint-induced movement therapy (CIMT) and treadmill locomotor training, showed better results. CONCLUSION: Emerging evidence reveals that the use of tDCS in individuals with CP is safe, feasible, easy to apply, tolerable, and effective when performed according to the recommendations available to date. The tDCS protocols in these studies were partially homogeneous, and sample sizes were generally small. More large-scale longitudinal studies are needed, particularly in individuals with ataxic and dyskinetic CP.