Postoperative nerve conduction changes after open and endoscopic carpal tunnel release

Abstract Objective : To assess the improvement of motor distal latency (MDL), sensory nerve conduction velocity (SCV) of the median nerve and the amplitudes of compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) in patients with idiopathic carpal tunnel syndrome subjected to surgical treatment according to the open carpal tunnel release method and the endoscopic carpal tunnel release. Methods : Sixty-six hands of sixty-six patients were divided into two groups: the ECTR group and the OCTR group. The patients were evaluated preoperatively, and at 1, 3, 6, and 12 months postoperatively. Results : Although no statistically significant difference of the recovery of MDL and the amplitude of CMAP and SNAP was detected between the two groups at any time point during follow-up, one patient in the ECTR group in whom the operation had been converted to OCTR, showed delay of MDL and decrease in the amplitude of CMAP. Conclusions : There is a risk of nerve damage in patients undergoing ECTR. Although statistical analysis suggests that nerve conduction improves by about the same degree 12 months after ECTR or OCTR, slightly faster improvement after OCTR cannot be excluded.