Specific features associated with femoral shaft fractures caused by low-energy trauma.

OBJECTIVE: To scrutinize the fracture patterns of femoral shaft fractures caused by low-energy injury mechanism and to delineate the problems associated with the treatment of these fractures.

MATERIALS AND METHODS: Of a total of 192 consecutive skeletally mature patients with 201 acute fresh femoral shaft fractures admitted during a 10-year period (1985-1994), 50 patients had a fracture caused by low-energy trauma. The fractures were classified in terms of their configuration, site, degree of comminution, and soft-tissue injury. The previous fractures, chronic illnesses, and continuous medications of the patients as well as the injury mechanisms and concomitant injuries were registered. All general and local complications and their consequences were recorded. Forty patients could be followed until the bony union of the fracture was achieved, the mean follow-up time being 14 months.

RESULTS: The incidence of these injuries was 2.5 per 100,000 person-years. There were 32 women and 18 men. The mean age of the patients was 65 years (range, 17-92 years). Thirteen patients were younger than 60 years of age. Thirty-two (64%) had at least one local or general factor weakening the mechanical strength of the bone that predisposed them to a fracture. Thirty-two patients sustained a fracture of the left femur (p < 0.05). All fractures were closed. None of the patients had significant concomitant injuries. In 33 cases, the site of the fracture was in the middle third of the femur. The fracture configuration was spiral in 29, transverse in 10, oblique-transverse in 7, and oblique in 4 cases. Postoperative complications, including delayed union, nonunion, and malunion, occurred with 29 patients. Eighteen reoperations among 12 patients were performed because of these complications.

CONCLUSIONS: Femoral shaft fractures caused by low-energy violence occur mainly in patients suffering from a chronic disease or a condition causing osteopenia of the femur. The most common fracture pattern was a spiral one in the middle third of the femoral shaft. Despite the low-energy violence, the treatment of these fractures is not devoid of complications. The treatment of these seemingly simple fractures requires careful planning and meticulous operative technique.