Affiliation: | 1. Spine Unit, Department of Orthopaedic Surgery, Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, 2100 Copenhagen, Denmark;2. Combined Neurosurgical and Orthopedic Spine Program, Vancouver General Hospital, University of British Columbia, Floor 6, Blusson Spinal Cord Center, 818 West 10th Ave., Vancouver, British Columbia V5Z 1M9, Canada |