Pathologic Fracture in Radiation-induced Osteosarcoma Misdiagnosed as Delayed Femoral Neck Fracture / 대한정형외과학회잡지

ABSTRACT

Secondary osteosarcoma has a relatively higher incidence in middle aged persons than in children. Radiation-induced osteosarcoma occurs in approximately 1% of patients who have been treated with more than 2,500 cGy. The time interval from radiation to onset of secondary osteosarcoma is approximately 10 to 15 years. A 51-year-old female who have been treated with radiation for angiomyxoma was hospitalized due to right hip pain. She had a minor trauma 2 weeks prior to hospitalization. A day before hospitalization, she experienced a second trauma by fall, and then, severe hip pain developed. A radiograph of the patient showed femoral neck fracture with sclerotic change of fractured margin. We diagnosed the patient as having a neglected femoral neck fracture and treated it with closed reduction using cannulated screw fixation. At 6 months post-surgery, the patient had residual pain of the right hip and we could find overproduced callus at the fracture site. Through further evaluation, we diagnosed this as secondary osteosarcoma with pulmonary metastasis. We report this case to make a warning about a misdiagnosed osteosarcoma as a simple femoral neck fracture.