Surgery versus corticosteroid injection for carpal tunnel syndrome (DISTRICTS): an open-label, multicentre, randomised controlled trial.

Background: Surgery and corticosteroid injections are established treatments for carpal tunnel syndrome, but the optimal treatment strategy remains unclear. This study aimed to compare starting treatment with surgery versus starting with a corticosteroid injection.

Methods: We conducted an open-label, randomised controlled trial across 31 hospitals in the Netherlands. Eligible patients, diagnosed with carpal tunnel syndrome for at least 6 weeks and confirmed by electrophysiological or sonographic testing, were randomly assigned (1:1) to start treatment with either surgery or an injection via a web-based system. Randomisation was stratified by unilateral or bilateral symptoms, carpal tunnel syndrome with or without concomitant disease as risk factor, and previous ipsilateral injections. If needed, additional treatments were allowed, such as additional injections or surgery. The primary outcome, assessed in the intention-to-treat population, was the proportion of patients who were recovered (defined as a score of less than eight points on the six-item carpal tunnel syndrome scale) at 18 months. The trial was preregistered with the ISRCTN Registry (ISRCTN13164336) and is now completed.

Findings: From Nov 7, 2017, to Nov 4, 2021, 934 participants (545 female and 389 male participants) were included. 468 were randomised to the surgery group and 466 to the injection group. At 18 months, 805 (86%) of 934 participants had primary outcome data. In the surgery group, 243 (61%) of 401 participants had recovered, significantly higher than the 180 (45%) of 404 participants recovered in the injection group (relative risk 1·36; 95% CI 1·19-1·56; p<0·0001). One or more adverse event occurred in 376 (86%) of 436 participants in the surgery group and in 384 (85%) of 453 participants in the injection group. One participant in the surgery group was hospitalised due to complications. No treatment-related deaths were reported.

Interpretation: In patients with carpal tunnel syndrome, initiating treatment with surgery offers a higher chance of recovery after 18 months compared with starting with a corticosteroid injection, even with the possibility of additional interventions.

Funding: The Netherlands Organization for Health Research and Development and Zorgverzekeraars Nederland.