抄録
We report a case of subchondral insufficiency fracture of the left femoral head which occurred after subcapital fracture of the right femoral head.
A 81-year-old woman, who was 143 cm in height, 60 kg in weight, and obesity (Body Mass Index (BMI); 29.3), has a history of hypertension, mild cerebral infarction, thyroid cancer (post-operation) and mild osteoporosis (Young Adult Mean 77%).
The patient complained of pain in the right hip joint in January 2004. A radiograph of the right hip joint showed no evidence of fracture and there was no history of trauma. Three months later, the patient had subcapital fracture of the right femoral head and underwent surgical replacement of the right femoral head.
After the operation, the patient was able to walk using a T cane. At four months after the operation, the patient complained of pain of the left hip joint without history of trauma. A radiograph of the left hip joint showed no evidence of fracture, although MR imaging demonstrated a subchondral area of low signal intensity on T1 and T2-weighted images, and a CT examination showed an irregular, sclerotic line on a subchondral region of the femoral head.
The diagnosis was subchondral insufficiency fracture of the left femoral head, and the patient underwent surgical treatment of the left femoral head. The pathological diagnosis was the reparative phase of fracture without malignancy and avascular necrosis of the femoral head.
It is necessary for us to observe the clinical course carefully even if the radiograph shows no evidence of fracture in such cases among older, obese female patient.
