Wound complications after cast immobilization compared to early functional treatment in surgical fixation of ankle fractures: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND: with the advance of early functional treatment, the use of post-operative cast immobilization of ankle fractures has decreased significantly. However, limited evidence suggests an increase in wound complications with early functional treatment. OBJECTIVE: to perform a systematic review and meta-analysis of randomized controlled trials to determine the incidence of wound complications after cast immobilization compared to early functional treatment in surgical fixation of ankle fractures in skeletally mature patients. METHODS: a systematic search of PubMed, Embase and Cochrane libraries was performed from 2000 to 2025 to identify randomized controlled trials comparing cast immobilization (> two weeks) with early functional treatment (≤ two weeks cast immobilization) after surgical fixation of ankle fractures in skeletally mature patients. Methodological quality was assessed using the RoB-2 for randomized controlled trials. The primary outcome was a composite overall incidence of any wound complication. Secondary outcome measures included 1) impaired wound healing (e.g. wound dehiscence, wound necrosis), 2) superficial infection, 3) deep infection, and 4) wound-related reoperations. Outcomes were pooled using a random-effects model to determine relative risks (RRs) with 95% confidence intervals (CIs). RESULTS: a total of 10 randomized controlled trials with 1142 skeletally mature patients were included. The cast immobilization group consisted of 544 patients and the early functional treatment group of 598 patients. Wound complications occurred in 35 (6%) patients in the cast immobilization group and 85 (14%) in the early functional treatment group (RR 2.14; CI 95% 1.38-3.34). Similarly, higher risk of impaired wound healing (10 [2%] vs. 26 [4%]; RR 2.03; CI 95% 1.36-3.01), superficial infection (23 [4%] vs. 49 [8%]; RR 1.87; CI 95% 1.21-2.89), but not for deep infection (2 [