1. Department of Orthopaedic Surgery; Johns Hopkins University School of Medicine; Baltimore Maryland 21205
2. Department of Neurosurgery; University of Maryland School of Medicine; Baltimore Maryland 21201
3. Department of Biomedical Engineering; Johns Hopkins University School of Medicine; Baltimore Maryland 21205
4. Department of Orthopedic Surgery; Zhong Shan Hospital, Fudan University; Shanghai China
5. Department of Anesthesiology and Critical Care Medicine; Johns Hopkins University School of Medicine; Baltimore Maryland 21205
6. Department of Orthopaedics; University of Maryland School of Medicine; Baltimore Maryland 21201
7. Department of Anatomy and Neurobiology; University of Maryland School of Medicine; Baltimore Maryland 21201