Supportive bandage, removable splint, or walking casts for low-risk ankle fractures in children: a feasibility randomized controlled trial

Aims: It is unclear if a supportive bandage, removable splint, or walking cast offers the best outcome following low-risk ankle fractures in children. The aim of this study was to evaluate the feasibility of a randomized controlled trial to compare these treatments.

Methods: Children aged five to 15 years with low-risk ankle fractures were recruited to this feasibility trial from 1 February 2020 to 30 March 2023. Children were randomized to supportive bandage, removable splint, or walking cast for two weeks. Follow-up at two, six, and 12 weeks was undertaken to determine feasibility for a definitive trial. Outcomes collected included complications, the Patient-Reported Outcomes Measurement Information System (PROMIS) mobility score, Paediatric Quality of Life Inventory, youth version of the EuroQol five-dimension health questionnaire, and Activities Scale for Kids - Performance.

Results: A total of 87 children from six hospitals were randomized at a rate of 0.9 participants per site per month. Two children in the supportive bandage group crossed over to an alternative device. Complications were reported in six children. One child in the cast group developed skin blisters. One child in cast and one in bandage sustained a reinjury during the 12-week follow-up, and two children (one splint and one cast) required additional immobilization after the two-week treatment for persistent pain. Of the 84 participants who remained in the study at six weeks, 43 (51.2%) returned follow-up questionnaires at six weeks. Of the patient-reported outcome measures (PROMs), proxy-reported PROMIS mobility showed good responsiveness, low ceiling effects, and low missing item rates. In an exploratory analysis, small differences were observed between groups, with no evidence that any of the treatments were superior.

Conclusion: This feasibility study showed acceptable recruitment and retention rates. There remains equipoise regarding the best treatment of these injuries. All three treatments appear well tolerated with similar complication rates. A primary outcome of complications or treatment failure would provide the highest study retention with secondary PROMs and economic analysis.