Collagenase injection versus limited fasciectomy surgery to treat Dupuytren's contracture in adult patients in the UK: DISC, a non-inferiority RCT and economic evaluation

Dupuytren's contracture is caused by nodules and cords which pull the fingers towards the palm of the hand. Treatments include limited fasciectomy surgery, collagenase injection and needle fasciotomy. There is limited evidence comparing limited fasciectomy with collagenase injection. To compare whether collagenase injection is not inferior to limited fasciectomy when treating Dupuytren's contracture. Pragmatic, two-arm, unblinded, randomised controlled non-inferiority trial with a cost-effectiveness evaluation and nested qualitative and photographic substudies. Thirty-one National Health Service hospitals in England and Scotland. Patients with Dupuytren's contracture of ≥ 30 degrees who had not received previous treatment in the same digit. Collagenase injection with manipulation 1-7 days later was compared with limited fasciectomy. The primary outcome was the Patient Evaluation Measure score, with 1 year after treatment serving as the primary end point. A difference of 6 points in the primary end point was used as the non-inferiority margin. Secondary outcomes included: Unité Rhumatologique des Affections de la Main scale; Michigan Hand Outcomes Questionnaire; recurrence; extension deficit and total active movement; further care/re-intervention; complications; quality-adjusted life-year; resource use; and time to function recovery. Online central randomisation, stratified by the most affected joint, and with variable block sizes allocates participants 1 : 1 to collagenase or limited fasciectomy. Participants and clinicians were not blind to treatment allocation. Between 31 July 2017 and 28 September 2021, 672 participants were recruited ( = 336 per group), of which 599 participants contributed to the primary outcome analysis ( = 285 limited fasciectomy; = 314 collagenase). At 1 year (primary end point) there was little evidence to support rejection of the hypothesis that collagenase is inferior to limited fasciectomy. The difference in Patient Evaluation Measure score at 1 year was 5.95 (95% confidence interval 3.12 to 8.77; = 0.49), increasing to 7.18 (95% confidence interval 4.18 to 10.88) at 2 years. The collagenase group had more complications ( = 267, 0.82 per participant) than the limited fasciectomy group ( = 177, 0.60 per participant), but limited fasciectomy participants had a greater proportion of 'moderate'/'severe' complications (5% vs. 2%). At least 54 participants (15.7%) had contracture recurrence and there was weak evidence suggestin