1. Department of Spine Surgery, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
2. Center of Experimental Orthopaedics, Saarland University Medical Center, Homburg, Saarland, Germany
3. Sino Euro Orthopaedics Network, Homburg, Saarland, Germany
4. Department of Pathology, Basic Medical College, Xinjiang Medical University, Urumqi, China
5. Frankfurt Initiative for Regenerative Medicine, Experimental Orthopaedics and Trauma Surgery, J. W. Goethe University, Frankfurt, Germany