Shaping in lower-limb CIMT: a critical review of technological innovation and clinical efficacy

Introduction Stroke-induced lower limb (LL) hemiparesis profoundly impacts mobility. While constraint-induced movement therapy (CIMT) is well-established and effective for upper limb rehabilitation, its application to the lower limb (LL-CIMT) remains underexplored. This narrative review examines shaping—a key behaviorist component of CIMT involving the reinforcement of progressively closer approximations to a target motor task—within LL-CIMT interventions. Objective To synthesize neurophysiological frameworks, clinical evidence (level I–IV), and technological advancements (2019–2024) from 9 studies to assess shaping’s impact on motor recovery, gait kinematics, and neuroplastic remodeling. Method A narrative synthesis of nine peer-reviewed studies (6 randomized controlled trials, 3 cohort studies) was conducted. Databases including PubMed, Scopus, and Web of Science were searched using keywords such as “LL-CIMT” and “shaping.” Studies were selected based on relevance to shaping within LL-CIMT, focusing on clinical efficacy, mechanistic insights, and technological applications. Results Analysis of nine studies demonstrated that shaping enhances motor recovery, gait dynamics, and neuroplasticity, evidenced by improved Fugl-Meyer Lower Extremity scores (Δ = 6.8, p < 0.001), stride length (Δ = 12.3 cm, 95% CI 9.8–14.8), and corticospinal tract fractional anisotropy (Δ = 0.15, p = 0.01). AI-driven exoskeletons and gamified telerehabilitation improved efficacy, though barriers included patient variability and resource limitations. Conclusion Shaping is integral to LL-CIMT but requires individualized protocols and scalable technologies. Future research should prioritize biomarker-driven interventions, 3D-printed exoskeletons, and policy reforms to optimize global accessibility.