1. Department of Radiology, Division of Musculoskeletal Imaging, Keck School of Medicine, University of Southern California, 1520 San Pablo St, Los Angeles, CA 90033.
2. Department of Radiology, Division of Musculoskeletal Imaging, University Hospitals of Cleveland, Case Western Reserve University, Cleveland, OH.
3. Department of Radiology, Allegheny General Hospital, Pittsburgh, PA.
4. Department of Radiology, Division of Nuclear Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA.
5. Department of Radiology, Division of Nuclear Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA.