Identifying Gaps in Rehabilitation Strategies for Chronic Stroke: A Systematic Review of Evidence in Patients With and Without Nerve Transfer.

BackgroundChronic stroke survivors often have persistent upper limb impairment. Two distinct therapeutic pathways have emerged: contralateral C7 (CC7) nerve transfer and technology-assisted/high-dose rehabilitation. Direct comparisons and detailed descriptions of rehabilitation protocols between these approaches are lacking.ObjectiveTo systematically compare upper limb rehabilitation strategies and outcomes in chronic stroke patients with versus without CC7 nerve transfer, and to identify key evidence gaps regarding rehabilitation dose, content, and delivery models.MethodsA systematic search of multiple databases and trial registries was conducted. Studies on technology-assisted rehabilitation (2016-2025) and CC7 studies (no date restriction) were included. Eligible studies involved adults with stroke and reported upper-limb rehabilitation strategies/outcomes. Evidence was grouped into: (1) CC7 studies, (2) RCTs of technology-assisted rehabilitation, and (3) systematic reviews/meta-analyses.Results48 studies were included. Non-surgical interventions (e.g., high-dose training, virtual reality, robotics) yielded small-moderate improvements, especially with high intensity/adherence. CC7 studies reported greater motor function gains and spasticity reduction, but postoperative rehabilitation protocols were poorly described, heterogeneous, and rarely quantified. No trial directly compared CC7 plus structured rehabilitation with optimized non-surgical programs. Most reviews were low quality, and RCTs had short follow-up.ConclusionsCC7 transfer should be framed as an adjunct to, not a substitute for, high-intensity rehabilitation. Future studies should validate integrated pathways pairing surgery with technology-assisted training, supported by standardized reporting of rehabilitation dose and durable outcomes.