Introduction: Femoral shaft fractures are commonly thought to be primarily associated with high-energy trauma in young persons. Only limited attention has been given to low-energy violence as a cause of these fractures among the elderly. National epidemiological data on characteristics of patients with femoral shaft fractures are lacking, so the purpose of this study was to analyse the incidence, admissions, causes of fracture and operations for these fractures on a nationwide basis in Sweden during 1998-2004. Patients and methods: Data on all femoral shaft fractures were extracted from the Swedish National Hospital Discharge Registry. Sex- and age-specific fracture incidence, hospital admissions, mechanisms of injury and surgical procedures were analysed using descriptive analysis, linear-regression analysis and other methods as appropriate. Results: Over a period of 7 years, 6409 patients with femoral shaft fractures were identified, corresponding to an annual incidence of 10 per 100,000 person-years. Men had a younger median age (27 years, IQR 12-68) than women (79 years, IQR 62-86) (p < 0.001). Females (54%) generated more admissions than males (46%). The incident rate ratio between men and women was 0.9 (p < 0.001). Most years of age, 2% of the fractures were open fractures. The total number of hospital admissions was stable during 1998-2004. The two major mechanisms of injury were falls on the same level (50%) and transport trauma. Osteosynthesis with femoral nail (54%) was the preferred operation, followed by osteosynthesis with plate and screws (16%), skeletal traction (14%) and external fixation (6%). Discussion: This nationwide study on femoral shaft fractures provides an update on incidence, admissions, external causes and surgical procedures. This information assists health-care providers in planning hospital beds, surgical interventions and risk preventions. Moreover, these data can be used for power calculations for further clinical studies.