Incidence and Risk Factors for Surgical Site Infection in Ankle Fractures: An Observational Study of 480 Patients in Sweden

Introduction: Surgical site infection (SSI) is a frequently reported complication after ankle fracture surgery. To our knowledge, no study has been conducted on its incidence in Sweden. The present study aimed to determine the incidence of, risk factors for, and most common causative pathogen of SSI. Methods: Patients who underwent primary surgery for an ankle fracture between 1 September 2017 and 31 August 2019 at the Sahlgrenska University Hospital were identified. Data on potential SSI risk factors and clinical outcome (infected/non-infected) were retrieved from medical records. Cox regression analysis and descriptive statistics were used. Results: Of the 480 reviewed patients, 49 developed SSI (10.2%), of which 35 (7.3%) were superficial and 14 (2.9%) were deep. Open fractures (p < 0.001) and age (p = 0.016) were statistically significant risk factors for SSI in the univariate analysis. In the multivariable analysis, only open fracture was statistically significant (HR = 3.0; 95% C.I. = 1.3–6.9, p = 0.013). Cases of Staphylococcus aureus (S. aureus) were most common (n = 12, 24.5%). Methicillin resistance was uncommon (n = 2, 4.1%). Conclusions: An incidence of 10.2% was established, which is comparable to international findings. Infection monitoring is an important part of tackling the global challenge of antibiotic resistance. Future prospective studies to further establish risk factors are warranted to decrease the incidence of SSI.