Increased mortality after lower extremity fractures in patients <65 years of age

Background and purpose — The association between mortality and lower extremity fractures (other than hip fractures in older individuals) is unclear. We therefore investigated mortality in adults of all ages after lower extremity fractures that required inpatient care. Patients and methods — Diagnosis code (ICD10), procedure code (NOMESCO), and 7 additional characteristics of patients admitted to the trauma ward at Central Finland Hospital were collected between 2002 and 2008 (n = 3,567). Patients were followed up until the end of 2012. Mortality rates were calculated for patients with all types of lower extremity fractures using data from the population at risk. Results — During the study, 2,081 women and 1,486 men sustained a lower extremity fracture. By the end of follow-up (mean duration 5 years), 42% of the women and 32% of the men had died. For all lower extremity fractures, the standardized mortality ratio (SMR) was 1.9 (95% CI: 1.8–2.0) for women and 2.6 (CI: 2.4–2.9) for men. In patients aged ≥65 years, mortality was increased and of similar magnitude after fractures of the hip, femoral diaphysis, and knee (distal femur, patella, and proximal tibia). In patients aged <65 years, mortality was increased after fractures at all sites. The SMR after fractures at different sites ranged between 2.1 (CI: 1.4–3.2) (ankle) and 6.7 (CI: 5.0–9.0) (hip) in patients aged <65 years and between 0.6 (CI: 0.30–1.1) (leg) and 2.2 (CI: 2.0–2.3) (hip) in patients aged ≥65 years. Interpretation — The post-fracture SMR of patients aged <65 years was at least double that of older patients. Furthermore, the higher mortality observed after proximal fractures of the lower extremity was greater in younger patients. The reasons behind these findings remain unclear.