Prospective randomized controlled trial: early weight bearing after conservative treatment of Weber B ankle fractures (pancake trial)

Eur J Orthop Surg Traumatol. 2024 Jan;34(1):591-598. doi: 10.1007/s00590-023-03651-6. Epub 2023 Sep 2.

Abstract

Purpose: Different studies have shown that weightbearing is safe in stable transsyndesmotic, isolated lateral simple ankle fractures. Despite this evidence, AO guidelines still recommend immobilization with above-the-knee cast for 4-6 weeks for these fractures. The objective of this study was to compare the outcomes of mobilization and weightbearing to those of immobilization and non-weightbearing in patients with stable transsyndesmotic, lateral isolated simple ankle fractures.

Methods: Fifty patients were randomly assigned to permissive weightbearing in a walking boot or non-weightbearing immobilization using a below-the-knee cast. Primary outcome was ankle functionality as scored by the Olerud-Molander Ankle Score (OMAS). Secondary outcomes were radiological displacement of fracture, range of motion (ROM), calf circumference, and RAND 36-item health survey. Patients were in follow-up for 24 months.

Results: Ankle functionality after six and twelve weeks was significantly higher for the intervention group, with respectively 30 points (p = 0.001) and 10 points (p = 0.015) of difference. ROM improved significantly in the intervention group after six weeks. All fractures showed radiological progression of fracture healing. RAND 36-item showed differences in both physical (60.3 vs. 46.3, p = 0.017) and mental (78.5 vs. 58.2, p = 0.034) components in favor of the intervention group. In 16% of patients who initially showed stable fractures on radiographic imaging, joint dislocation was identified on weightbearing radiographs prior to randomization, leading to exclusion.

Conclusion: Weightbearing and mobilization using a walking boot may be a safe treatment for patients with stable Weber B fractures.

Keywords: Cast; Functionality; Lateral transsyndesmotic ankle fracture; Permissive weightbearing; Walking boot.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Ankle Fractures* / diagnostic imaging
  • Ankle Fractures* / therapy
  • Conservative Treatment
  • Fracture Fixation, Internal / methods
  • Fracture Healing
  • Humans
  • Prospective Studies
  • Treatment Outcome
  • Weight-Bearing