1. Orthopaedic Research Laboratory, Department of Biomedical Engineering; Virginia Commonwealth University; P.O. Box 843067 Richmond Virginia
2. Department of Orthopaedic Surgery; Virginia Commonwealth University; Richmond Virginia
3. Department of Biostatistics; Virginia Commonwealth University; Richmond Virginia
4. Department of Radiology; Virginia Commonwealth University; Richmond Virginia
5. Department of Orthopaedic Surgery; Duke University; Durham North Carolina