Affiliation: | 1. Department of Neurosurgery, Second Hospital of Hebei Medical University, Shijiazhuang, China;2. Department of Orthopedics, Third Hospital of Hebei Medical University, Shijiazhuang, China;3. Departamento dental, Complejo Hospitalario de la Universidad de Santiago de Compostela, A Coru?a, Spain;4. Department of Orthopedics, First Hospital of Shanghai Jiao Tong University School of Medicine, Shanghai, China |