M-C Hsieh1, W-S Huang1,2, C-C Chin1,2, Y-H Kuo1,2, K-T Peng3,4. 1. Division of Colon and Rectal Surgery, Department of Surgery, Chang Gung Memorial Hospital, Chiayi, Taiwan. 2. Graduate Institutes of Clinical Medical Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan. 3. Graduate Institutes of Clinical Medical Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan. mr3497@cgmh.org.tw. 4. Division of Joint Reconstruction, Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Chiayi, Taiwan. mr3497@cgmh.org.tw.