Abstract
OBJECTIVE: Carpal tunnel syndrome (CTS) can drastically impair one's ability to work and interferes with activities of daily living. We recently demonstrated that, in rodents, conditioning electrical stimulation (CES) delivered to the nerve 7 days prior to surgery imparts a conditioning lesion-like effect by accelerating the rate of regeneration along the entire length of the nerve. The goal of this study is to test the hypothesis that CES could accelerate nerve regeneration and improve function in patients with moderate or severe CTS. METHODS: Using a double-blind randomized controlled study design, patients received surgery + CES or surgery + sham stimulation. They were evaluated at regular intervals for 12 months following intervention. Primary outcome was motor unit number estimation (MUNE), supplemented with secondary outcomes including motor and sensory nerve conduction studies, Semmes Weinstein Monofilaments, and Moberg Pick-Up Test. RESULTS: Sixty-four participants were randomized to either the treatment or control groups. There was no significant demographic or physiological difference at baseline between the groups. No major adverse event was found with treatment. Following intervention, there was significantly greater increase in MUNE of 62 ± 71 in the treatment group compared to 25 ± 66 in the controls after 12 months. In the treatment group, there was correspondingly better physiological and functional recovery and hand dexterity compared with the controls. INTERPRETATION: CES is a safe, feasible, and efficacious treatment to improve nerve reinnervation and functional outcomes in patients with moderate or severe CTS. This may open future possibilities for more effective treatment for other peripheral nerve injuries. ANN NEUROL 2026;99:1251-1262.