Hand surgeons performing more open carpal tunnel releases do not show better patient outcomes

Background: Although previous studies have shown that more experienced surgeons have better patient outcomes following a variety of procedures, in hand surgery and carpal tunnel release in particular, this relation remains unproven. The authors assessed whether there is an association between surgeon volume and patient outcomes following open carpal tunnel release. Methods: Patients who underwent carpal tunnel release between 2011 and 2015 at outpatient hand surgery clinics in The Netherlands were included. Surgeon annual volume was defined as the average number of carpal tunnel releases performed per year per participating surgeon over the study period. Primary outcome measures were the Symptom Severity Scale and Functional Status Scale of the Boston Carpal Tunnel Questionnaire 6 months postoperatively. Multilevel random intercept linear regression analyses were performed to assess whether there was an association between surgeon annual volume and outcome measures, with adjustment for patient characteristics, concomitant procedures, and intake score on the Boston Carpal Tunnel Questionnaire. Results: A total of 1345 patients were included, operated on by 17 surgeons. Median annual surgeon volume was 75 (interquartile range, 50 to 149). Only 0.5 to 0.6 percent of the total variance in patient outcome on the Boston Carpal Tunnel Questionnaire could be explained by random differences between surgeons. The authors did not find an association between annual surgeon volume and outcome measures 6 months postoperatively (Symptom Severity Scale: β = 0.000; 95 percent CI, −0.001 to 0.001; and Functional Status Scale: β = 0.000; 95 percent CI, −0.001 to 0.001). Conclusion: In the authors’ sample of highly specialized hand surgeons operating in high-volume centers, they found no differences in outcome between high- and low-volume surgeons.