1. Department of Orthopaedics, The Third Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, People's Republic of China;
2. Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China;
3. Department of Orthopaedics, The First Affiliated Hospital of Guangxi University of Chinese Medicine, Nanning, Guangxi, People's Republic of China