The original version of this article unfortunately contained one mistake. The institutions of the authors are wrong. The corrected institutions are given below.Zhi-cai DU1, 2, Li-xin ZHU11Department of Spinal Surgery, Orthopaedic Medical Center, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China 2Department of Minimally Invasive Spinal Surgery, The Second Affiliated Hospital of Inner Mon-golia Medical University, Hohhot 010030, China.