1. Center for Biomedical Engineering Research, Department of Mechanical Engineering, University of Delaware, Newark, Delaware.
2. Bone and Cartilage Research Laboratory, Nemours Biomedical Research, Department of Orthopaedics, Alfred I. duPont Hospital for Children, Wilmington, Delaware.
3. Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania.
4. Department of Clinical Science, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, Pennsylvania.