Liu Jun1,2, Fu Xin1,2, Han Zhe1,2, Li Zhi-jun3,4. 1. Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, 300052, China. 2. Department of Orthopedics, Tianjin Hospital, Tianjin, 300211, China. 3. Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, 300052, China. hansontijmu@gmail.com. 4. Department of Immunology, Tianjin Medical University, Tianjin, 300070, China. hansontijmu@gmail.com.