Complications After Ankle Fracture Surgery in Finland Between 1998 and 2020

Background: Ankle fracture is a common injury and often requires operative treatment. This study investigated short-term (<= 4 months) and long-term (>4 months) complications after ankle fracture surgery in a 23-year period with use of data from a comprehensive, nationwide, individual-level register. Methods: Data regarding patients who underwent operative treatment for ankle fracture were collected from the Finnish Care Register for Health Care and analyzed with use of logistic and Cox regression. Results: A total of 83,666 ankle fractures were operatively treated between 1998 and 2020. Of these, 36% were lateral malleolar fractures, 7% were medial malleolar fractures, 52% were bimalleolar or trimalleolar fractures, and 5% were other types of fractures. Fifty-one percent of the fractures were in female patients. The overall rate of short-term complications was 7.2%. Specifically, infection occurred in 4.4% of cases; thromboembolic complications,1.6% of cases; mechanical complications, 0.4% of cases; and other complications, 0.9% of cases. An age of >75 years was associated with a higher rate of short-term complications than an age of 51 to 75 years, with an odds ratio of 1.53 in the multivariable analysis (95% confidence interval, 1.39 to 1.67; p < 0.001). Short-term complications were also more prevalent in patients with diabetes (with or without associated complications); chronic pulmonary, kidney, or liver disease; or peripheral vascular disease. Mortality during the first 4 months after the ankle fracture operation was 0.6%. The most common reason for reoperation in the long term (>4 months after the index procedure) was fixation device removal, with a cumulative incidence of 17% within the first 3 years postoperatively. The risk of implant removal increased in younger patients and patients with bimalleolar or trimalleolar fractures. The cumulative incidence of ankle arthrodesis and arthroplasty was low. Conclusions: Although postoperative complications are relatively rare, their treatment can lead to considerable morbidity. The findings of this study allow us to identify patients who are prone to complications or reoperations after undergoing operative treatment for ankle fracture. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.