Median nerve damage during two-portal endoscopic carpal tunnel release

Objective: To evaluate the adverse effects of Chowʹs two-portal endoscopic carpal tunnel release (ECTR) performed by an experienced surgeon on median nerve function in patients with idiopathic carpal tunnel syndrome, as compared to open carpal tunnel release (OCTR). Methods: Eighty-seven hands subjected to ECTR and 65 hands subjected to OCTR were reviewed. Both groups of patients were similar with regard to age, gender, and severity of the disease. Both groups were compared for the number of hands showing worsening of motor distal latency, sensory conduction velocity, and sensory disturbance after surgery. Results: Thirteen hands of 12 patients showed worsening of median nerve function after ECTR, while only one hand showed worsening after OCTR. This difference was statistically significant (p=0.0041). Conclusions: Median nerve damage, although transient or not serious, may occur even if the procedure is done correctly.