Early weight bearing and mobilization decrease perioperative complications in patients after ankle fracture; the retrospective multicenter (TRON group) study

Open reduction and internal fixation (ORIF) for unstable ankle fractures (AF) are relatively predictable with excellent outcomes. Rehabilitation strategies are still being debated after surgical intervention for AF: non-weight bearing and cast immobilization for six weeks after the surgical repair of unstable AF or early functional treatment with partial weight bearing. This study aimed to compare early weight bearing and functional outcomes and complications. Between April 2014 and March 2019, 1421 patients with AF underwent ORIF at 11 institutions (TRON group). The patients were divided into two groups: Group E started weight bearing within six weeks after surgery, and group L started weightbearing for more than six weeks after. To adjust for baseline difference between groups, a propensity score-matched algorithm was used to match Group E with Group L in a 1:1 ratio of 294 cases each. We compared the American Orthopedic Foot and Ankle Society (AOFAS) score as the functional outcome, the rate of wound dehiscence, superficial and deep infections, blistering, nonunion, neurapraxia, and reoperation at 3, 6, and 12 months after surgery. The mean period of non-weight bearing was significantly shorter in group E (3.68 ± 1.02 vs. 6.67 ± 1.43; P < 0.001). The mean period of cast immobilization term were shorter in group E (1.84 ± 1.35 vs. 2.65 ± 1.51; P < 0.001). There were no differences in the AOFAS score at any period. The rates of deep infection and reoperation in Group E were significantly lower than those in Group L (1.7% vs. 6.1%; P = 0.009, 2.0% vs. 7.8%; P = 0.002, respectively). There were no significant differences in superficial infection (9 vs. 15; P = 0.297), nonunion (9 vs. 15 P = 0.30), blistering (4 vs. 3; P = 1.00), neurapraxia (2 vs. 1; P = 1.00), and wound dehiscence (15 vs. 18; P = 0.72). Although functional outcome was similar depending on whether early weight bearing was allowed, the rates of deep infection and reoperation decreased in patients with early weight bearing. We recommend early postoperative weight bearing in patients with a surgically treated AF.