1. Department of Neurosurgery, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
2. Spine Center, Sanbo Brain Hospital, Capital Medical University, Beijing, China
3. Department of Neurosurgery, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
4. Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China