Outcome, severity of injury and length of sick leave after an ankle fracture: an observational register study.

There is a lack in understanding the reasons for different lengths of sick leave in patients who sustain ankle fractures. The aim of this study is to examine variations in the length of sick leave in ankle fracture patients and how treatment, type of ankle fracture and the patient-reported outcome are associated with the length of sick leave. In this study were data from the Swedish Social Insurance Agency (SSIA) and the Swedish Fracture Register (SFR), combined. Patients who sustained an ankle fracture were identified and the length of the sick leave calculated. Variables associated to the length of the sick leave were analysed. Fifty-three percent of the patients were on sick leave for an average of 88 days. Factors that were associated with the length of sick leave were an open fracture, operative treatment, multiple treatments, AO/OTA classification, and previous sick leave. Patients on sick leave for 22 weeks or more scored 15 points (CI 95% 12-18) worse on the dysfunction index of the Short Musculoskeletal Function Assessment in the 1-year follow-up compared to the pre- injury survey. This can be compared to 3 points (CI 95% 2-5) lower in patients with the shortest sick leave. There is an association between the severity of the injury and the length of sick leave following an ankle fracture, as well as between the patient-reported outcome after one year and the length of the sick leave.