Intraoperative Nerve Conduction Studies During Open Carpal Tunnel Release: A Pilot Study.

Background: Operative management of carpal tunnel syndrome (CTS) involves release of the transverse carpal ligament (TCL) and often the volar antebrachial fascia (VAF). Evidence of a difference between TCL and TCL+VAF release is limited. We conducted a pilot study to measure changes of intraoperative nerve conduction velocity (NCV) after CTS surgery and compared outcomes of variable degrees of decompression. Methods: Patients aged 18 to 65 years diagnosed with idiopathic CTS that failed to respond to conservative management were included in this study. Patients were excluded if they had prior surgical release, diabetes, acute CTS, trauma, or cervical spine radiculopathy. Outcomes included motor and sensory amplitude and latency. Electrodes were placed on the skin intraoperatively along the abductor pollicis brevis, index finger, and forearm. Outcome data were recorded at baseline, after TCL release, and after TCL+VAF release. Data were compared using a single-tail t test. Results: A total of 10 patients were included in this study. There were no significant changes in mean motor or sensory amplitude and latency from baseline to TCL release, TCL to VAF release, or from baseline to TCL+VAF release measured intraoperatively. Conclusions: This pilot study shows there is no immediate detectable difference in NCV following release of TCL or TCL+VAF. This suggests that NCV may not be useful for assessing intraoperative improvement. We highlight the need for future research in the form of case-control studies to determine the utility of intraoperative NCV. These studies should be conducted with larger numbers of patients and involve multiple hand specialists.