Endoscopic Release Superficial Rather Than Deep to the Transverse Carpal Ligament for Carpal Tunnel Syndrome Improves Immediate Postoperative Transient Symptomatic Exacerbation With Fewer Absences From Work.

PURPOSE: To determine the endoscopic release superficially rather than deep to the transverse carpal ligament to reduce the incidence of transient symptomatic exacerbation and postoperative absence from work in patients with carpal tunnel syndrome. METHODS: From January 2012 to January 2018, patients with idiopathic carpal tunnel syndrome who underwent one-portal endoscopic release superficial to the transverse carpal ligament (ERSTCL) were analyzed. For comparison, a cohort treated with the conventional Chow endoscopic release between February 2008 and October 2013 were included. Transient worsening of symptoms, discrimination sensation, and days off work were assessed. The minimal clinically important difference was calculated for discrimination sensation. Severity of symptom and functional status also were assessed using the Levine-Katz Questionnaire. Significance was set at P < .05. RESULTS: There was a significant difference between the ERSTCL group and the control group regarding the incidence of symptomatic exacerbation 1 week after surgery (2% vs 9%; P = .003) but no difference in other time intervals within the initial 3 months. There was a significant difference in 2-point discrimination 1 week (mean change = -0.13, 95% confidence interval [CI] -0.30 to 0.04, P = .01) and 2 weeks after surgery (mean change = -0.18, 95% CI -0.36 to -0.01, P = .033). Postoperative 1 and 2 weeks, 28% and 35% patients in ERSTCL group achieved a minimal clinically important difference, respectively. Compared with control group, the difference in frequencies was statistically significant (28% vs 45%; P = .027; 35% vs 57%; P = .015). The difference between the 2 groups in postoperative absence from work was statistically significant (95% CI 1.083-4.724; P = .002), with an average reduction in sick leave of 3 days in ERSTCL group. At a mean follow-up of 3 years, no significant difference was found between the groups regarding symptom and function statuses. CONCLUSIONS: Endoscopic release superficial rather than deep to transverse carpal ligament for carpal tunnel syndrome improves immediate postoperative transient symptomatic exacerbation, which allows the patients to return to work earlier. LEVEL OF EVIDENCE: Level III, retrospective comparative study.