1. Department of Orthopaedic Surgery, Hallym University Sacred Heart Hospital, Dongan-gu, Anyang, Korea (the Republic of)
2. Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, Korea (the Republic of)
3. Department of Neurosurgery, Hallym University Sacred Heart Hospital, Anyang, Korea, Republic of
4. Department of Orthopaedic Surgery, Hallym University Dongtan Sacred Heart Hospital, Gyeonggi-do, Korea (the Republic of)