Shown are screening coronal T1-weighted images (left) and corresponding fat-suppressed T2-weighted images (right). A. Unilateral osteonecrosis in one patient. B and C. Bilateral osteonecrosis in two patients. In addition to having the curvilinear lesions of osteonecrosis, the patient at bottom (panel C) has increased signal in the head and neck of the left femur, consistent with edema surrounding the area of osteonecrosis. The patients in panels B and C developed symptoms after study enrollment.

Shown are high-resolution T1-weighted images (left) and corresponding fat-suppressed T2-weighted images (right). A. Coronal view of a wedge-shaped lesion of the anteromedial femoral head. B. Saggital view of a small subchondral lesion of the anterior superior aspect of the femoral head. C. Axial view of a large curvilinear lesion of the femoral head.