1. Department of Orthopedic Surgery, Yeouido St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, 10, 63-Ro, Seoul 07345, Republic of Korea
2. Department of Orthopedic Surgery, Incheon St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, 56, Dongsu-ro, Incheon 21431, Republic of Korea
3. Department of Statistics and Actuarial Science, Soongsil University, 369, Sangdo-ro, Seoul 06978, Republic of Korea