1. Department of Neurosurgery, Prince Mohammed Bin Abdulaziz Hospital, Riyadh, Saudi Arabia
2. Department of Neurosurgery, Mansoura University, Mansoura, Egypt
3. Department of Diagnostic Radiology, Prince Mohammed Bin Abdulaziz Hospital, Riyadh, Saudi Arabia
4. Orthopaedic Surgery, Rothman Orthopedic Institute, Philadelphia, PA, USA