SLR - May 2022 - Zohaib Moon, DPM
Reference: Kearney, R., McKeown, R., Parsons, H., Haque, A., Parsons, N., Nwankwo, H., ... & Costa, M. (2021). Use of Cast Immobilisation Versus Removable Brace in Adults with an Ankle Fracture: Multicentre Randomised Controlled Trial. BMJ, 374.Level of Evidence: Level 1
Scientific Literature Review
Reviewed By: Zohaib Moon, DPM
Residency Program: Northwest Medical Center – Margate, FL
Podiatric Relevance: Ankle fractures represent roughly 23 percent of lower extremity trauma, making them the most common fractures dealt with by Podiatric surgeons. While open reduction with internal fixation (ORIF) is considered the standard treatment in most cases, there remains controversy regarding postoperative protocols. Traditionally fiberglass casting was commonly prescribed, however, a recent shift towards removable Controlled Ankle Motion (CAM) boots have been customary. Newer literature supports the theory that functional bracing might reduce activity limitation, pain, and improve ankle movement. However, these potential advantages need to be balanced against the increased incidence of adverse events. The purpose of this study was to assess function, quality of life, and complications in adults treated with plaster cast immobilization versus a removable brace for ankle fractures.
Methods: The study was designed as a multicenter randomized control trial, evaluating 20 trauma units in the UK National Health Service. This study yielded a total of 669 adults with an acute ankle fracture suitable for cast immobilization. Three hundred thirty-four (334) were randomized to a plaster cast and 335 to a removable brace. Both interventions were required for a minimum of three weeks. The cast group was allowed ankle ROM once the cast was removed versus the bracing group who was encouraged to initiate ankle ROM exercises immediately.
The studies’ primary outcome was the Olerud Molander ankle score at 16 weeks. This scoring system is a self-administered questionnaire consisting of nine factors: pain, stiffness, swelling, stair climbing, running, jumping, squatting, supports, and work or activities of daily living. Secondary outcomes were complications, resource use, quality of life measures, and leg specific functional scores (Manchester-Oxford). Statistically, a linear regression analysis was utilized to assess differences in the Olerud Molander score between the two interventions.
Results: Five hundred two (75 percent) participants completed the study. All participants had a clear ankle fracture on a radiograph, with 93 percent showing lateral malleolar involvement, 29 percent medial malleolar involvement, and 18 percent posterior malleolar involvement. No statistically significant difference was found in the Olerud Molander ankle score between the cast and brace groups at 16 weeks. Nor was there a clinically relevant difference found at the six-week and 10-week time points. No clinically relevant differences were found in the disability rating index, Manchester-Oxford foot questionnaire, or EQ-5D-5L secondary outcomes at any time point
Conclusions: The authors of this study conclude that there is no difference between traditional cast immobilization and removable bracing for acute ankle fractures in adults. While the results are clear in this study, I personally believe there is a middle ground which incorporates benefits from both interventions. For my patients I’d prefer an initial two- to four-week period of immobilization with casting/splinting to provide maximum support and a rigid construct to optimize bone healing. This can be followed by a late stage of bracing and rehabilitation, decreasing the incidence of stiff joints, atrophied muscles, and even deep vein thrombosis. This article will help me treat my next patient by providing me with comfort in the fact that early, protected weightbearing is a viable and safe option to get my patients back on their feet.