A study protocol for a randomised trial of bracing after ankle fracture

Ankle fractures are common and debilitating injuries usually treated with immobilisation using a foot-ankle brace (walker). Emerging evidence suggests that a less restrictive ankle stirrup may accelerate recovery without increasing complications, and patients tend to prefer ankle stirrups. However, evidence supporting their non-inferiority is inconclusive. The aim of this study is to assess whether ankle stirrups are non-inferior to walkers in improving function and pain measured by the Manchester-Oxford Foot Questionnaire three months after ankle fracture.

The trial will be a two-phase, multicentre, pragmatic, non-inferiority randomised controlled trial. Patients ≥ 18 years with surgically or non-surgically treated ankle fractures will be included. A three-month pilot phase will assess trial feasibility, including recruitment rates. The full trial will randomise a maximum of 1,400 patients. The sample size is estimated to be sufficient to assess non-inferiority in the overall population and to explore non-inferiority in six subgroups stratified by sex and age (males 18-39 years, males 40-59 years and 60+ years) and treatment (surgical or non-surgical).

The bracing after ankle fracture trial will determine whether ankle stirrups are non-inferior to walkers in terms of patient-reported function and pain. Secondarily, the study will assess whether the ankle stirrup facilitates faster recovery of function, earlier return to work, and reduced healthcare costs. Findings will support evidence-based decision-making with respect to patient preferences.

Independent Research Fund Denmark, Grant no. 10.46540/4308-00191B.

NCT07163091.