1. Department of Surgery, Division of Neurosurgery and Spinal Program, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada
2. Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
3. These authors contributed equally to this work.
4. Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan
5. Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan