One week versus three to five weeks of plaster cast immobilization for nonreduced distal radius fractures, a cost effectiveness analysis embedded in a stepped wedge cluster randomized controlled trial

Objective Distal radius fractures are commonly seen at the Emergency Department. In the Netherlands, non- or minimally displaced fractures are immobilized for 3–5 weeks. However, evidence suggests shorter immobilization yields similar or better functional outcome. There is a lack of cost-effectiveness studies investigating shorter duration of cast immobilization. This study investigates the cost-effectiveness of one week of plaster cast immobilization versus three to five weeks. Methods Cost-effectiveness data was collected as part of the Cast-OFF 2 study which started the 1st of January 2022. A randomized stepped wedge cluster design was used with 11 hospitals, and 10 clusters, including patients with an isolated non- or minimally displaced distal radius fracture without fracture reduction. Costs on medical consumption, and productivity were scored with the local Electronical Patient Record, and questionnaires at week one, six, month six, and twelve. Cost-effectiveness was reported per Quality-Adjusted Life Year (QALY). Results A total of 402 patients were included (control n = 197 vs intervention n = 205). No differences in QALY were observed (+ 0.02, CI [-0.02, 0.06]). Cost savings for the intervention group ranged from €31.94 to €322.41 depending on different scenarios. The future perspective scenario with reduction of one outpatient clinic visit showed a significant cost saving of €254.27 (CI [-467.33, -41.21]). No significant differences were observed in baseline characteristics. Conclusion One week of plaster cast immobilization for non- or minimally displaced distal radius fractures results in comparable or better cost savings compared to usual care. Adopting one week of cast immobilization as the new standard-of-care could reduce healthcare costs. Trial registration Netherlands Trial Register NL9278. CMO: 2–21-7308.