1. Department of Neurosurgery, Hokkaido University Graduate School of Medicine
2. Department of Neurosurgery, Sapporo Azabu Neurosurgical Hospital
3. Department of Pathology, Hokkaido University Hospital
4. Department of Advanced Medicine for Spine and Spinal Cord Disorders, Hokkaido University Graduate School of Medicine
5. Department of Spinal Reconstruction, Hokkaido University Graduate School of Medicine