Analysis of Electrodiagnostic Recovery after Carpal Tunnel Release: A Retrospective Study

Objective: We investigated the factors affecting electrodiagnostic (EDX) parameters after carpal tunnel release (CTR).Methods: Thirty-nine cases with clinically diagnosed carpal tunnel syndrome who received CTR and EDX studies before and after CTR were enrolled in this study. We analyzed EDX parameters such as distal onset latency and the amplitude of median compound motor action potentials (CMAPs) and sensory nerve action potentials (SNAPs).Results: Among 39 cases, 24 (61.5%) showed improvement of at least 1 grade, based on Bland’s scale, after CTR. Follow-up EDX studies were performed 6 to 36 months after CTR. Improvement on Bland’s scale was shown in 50% of patients who received follow-up EDX studies at 6 and 12 months after CTR and in all patients who received follow-up at 24 and 36 months. The EDX parameters showed significant recovery. Younger patients showed greater recovery of SNAP amplitude (p = 0.021, r = -0.369) after CTR. The preoperative severe group showed greater recovery of CMAP (both amplitude and latency) than the non-severe group (p = 0.011 and p = 0.038, respectively).Conclusion: We confirmed the effectiveness of CTR through EDX studies. Age and preoperative EDX severity can affect the recovery of EDX parameters after CTR.