Omar A Al-Mohrej1, Sahar S Aldakhil2. 1. O. A. Al-Mohrej, Department of Orthopedic Surgery, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. 2. S. S. Aldakhil, Department of Orthopedic Surgery, King Abdulaziz Medical City, Riyadh, Saudi Arabia.