Open compared with 2-portal endoscopic carpal tunnel release: a 5-year follow-up of a randomized controlled trial.

PURPOSE: The purpose of this investigation was to extend the previously reported short-term randomized trial of open and endoscopic carpal tunnel release in patients with carpal tunnel syndrome (CTS) to compare outcomes 5 years after surgery. METHODS: In a single-center randomized controlled trial, 128 patients (25 to 60 years) with clinically diagnosed and electrophysiologically confirmed idiopathic CTS were randomized immediately before surgery to open or 2-portal endoscopic release. The outcome measures included the validated CTS questionnaire's symptom severity and functional status scales (scored from 1 to 5) completed at baseline and 1 year postoperatively. At the extended follow-up of the trial 5 years after surgery, 2 patients had died and the other 126 participants (63 patients in each group) completed the CTS questionnaire. RESULTS: At the 5-year follow-up no difference between the groups was found in the CTS symptom severity score. The mean (SD) score in the open group was 1.42 (0.7) and in the endoscopic group was 1.45 (0.7), and the mean difference in score change from baseline was 0.03 (95% confidence interval, -0.21 to 0.27). Between 1 year and 5 years postoperatively, the CTS symptom severity score had deteriorated by at least 0.4 point in 9 patients in the open group and in 10 patients in the endoscopic group. The mean (SD) CTS functional status score was 1.29 (0.5) in the open group and 1.30 (0.5) in the endoscopic group. At 5 years, 11 patients in the open group and 10 patients in the endoscopic group reported persistent pain in the scar or proximal palm. Three patients in each group had repeat surgery on the operated hand because of persistent or recurrent symptoms. CONCLUSIONS: The improvements in symptoms of CTS and hand-related disability 5 years after open and 2-portal endoscopic carpal tunnel release were equivalent. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic I