Fig. 2. A 28-year-old woman had osteonecrosis in the left femoral head. (A) Preoperative anteroposterior hip radiograph. (B and C) The angle of the necrotic area in the mid-coronal images of computed tomography and magnetic resonance imaging was 110°. The angle between the central vertical line of the femoral head and the lateral margin of the necrotic portion was 150°. (D) Immediate postoperative anteroposterior hip radiograph after curved intertrochanteric varus osteotomy. (E) Follow-up radiograph taken 6 years after the operation showing no progressing collapse or osteophyte formation around the femoral head.