1. Department of Spine Surgery, Honghui Hospital, School of Medicine, Xi’an Jiaotong University, Xi'an, China
2. Department of Orthopedics, Yan’an University Medical School, Yan’an, China
3. Department of Shoulder and Elbow Joint, Honghui Hospital, School of Medicine, Xi’an Jiaotong University, China
4. Department of Psychiatry and Behavioral Sciences, School of Medicine, Johns Hopkins University, Baltimore, MD, U.S.A.