Bilateral femoral neck fractures after pelvic irradiation.

Our patient, who had no history of trauma, developed bilateral femoral neck fractures several years after pelvic irradiation. The well-documented sequelae of femoral neck fractures include avascular necrosis, nonunion, and malunion. Postirradiation pelvic pain, particularly in the absence of trauma, should be aggressively evaluated. With high clinical suspicion and normal plain radiographs, MRI can be used to exclude potentially serious fractures.