1. Department of Spinal Surgery, The First Hospital of Shijiazhuang City, Shijiazhuang, Hebei 050011, P.R. China
2. Department of Spinal Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, P.R. China
3. Department of Rehabilitation Medicine, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, P.R. China