HAND-IN (hand function after neuromodulation and intensive training in children with cerebral palsy): study protocol for a randomized, triple-blind, controlled trial with embedded implementation and cost-effectiveness analyses

Abstract

ABSTRACT Aim The following clinical trial protocol aims to investigate the additional effects of bilateral transcranial direct current stimulation (tDCS) combined with constraint-induced movement therapy (CIMT) compared to CIMT alone in children and adolescents with spastic hemiparetic cerebral palsy. Methods This randomized, triple-blind, controlled trial will enroll 32 participants aged 7–16 years with spastic hemiparetic cerebral palsy (MACS I–II). Participants will be allocated to CIMT with sham or active bilateral tDCS (C3-C4, 1 mA, 20 min), with electrode placement guided by transcranial magnetic stimulation mapping. The intervention will last 3 weeks (5 days/week, 3 h/day). Primary outcomes will assess upper limb use (PMAL/TMAL). Secondary outcomes include dexterity (Box and Block Test), strength (dynamometry), functional performance (PAFT), and participation (COPM, GAS). Assessments will occur post-intervention and at 1, 3, and 6 months. Implementation of outcomes and cost-effectiveness will also be evaluated. Once completed, the study team will perform intention-to-treat analyses using linear mixed-effects models. Expected results The HAND-IN trial will provide evidence on the clinical, implementation, and economic effects of combining CIMT with bilateral tDCS in children with spastic hemiparetic cerebral palsy. If effective, this approach may enhance the durability of upper limb functional gains and support the adoption of neuromodulation in pediatric neurorehabilitation. Trial Registration Number (Brazilian Clinical Trials Record- REBEC): RBR-2fczbt2 (https://ensaiosclinicos.gov.br/rg/RBR-2fczbt2). Registration on January 15, 2026.