1. Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized commercial reproduction of this slide is prohibited Supplemental PowerPoint Slides Long-term follow up suggests spinal fusion is associated with increased adjacent segment disc degeneration but without influence on clinical outcome. Results of a combined follow-up from 4 RCTs. Anne F Mannion PhD1, Gunnar Leivseth MD PhD2, Jens-Ivar Brox MD PhD3, Peter Fritzell MD PhD4, Olle Hägg MD PhD5, Jeremy CT Fairbank MD FRCS6 1Spine Center, Schulthess Klinik, Lengghalde 2, 8008 Zürich, Switzerland 2Department Of Clinical Medicine, Neuromuscular Diseases Research Group, University of Tromsø, Norway 3 Departments of Physical Medicine and Rehabilitation and Orthopedics, Oslo University Hospital and Oslo University, Norway 4Neuroortopediskt Centrum, Länssjukhuset Ryhov, 551 85 Jönköping, Sweden 5Spine Center Göteborg, Gruvgatan 8, SE 421 30, V:a Frölunda, Sweden 6Nuffield Orthopaedic Centre, Oxford University Hospitals, Oxford, OX3 7HE, UK

2. Key-points The long-term radiographic follow-up (average 13 years) of 4 RCTs comparing fusion and non-operative care for patients with chronic LBP showed lower values for disc space height of the adjacent segment at LTFU in both groups compared with age and gender-adjusted norm values. Compared with the non-operative group, the fusion group showed a slightly but significantly lower disc space height at the adjacent segment (cranial) and the segment above that. There was no relationship between adjacent segment disc space height at long-term follow up and either Oswestry Disability Index scores or LBP intensity.

3. Unadjusted mean values (with 95% CI) for disc space height in the two treatment groups at each of the vertebral levels examined. Index level = level (or uppermost of levels) originally planned for fusion, should the patient have been randomized to the fusion group. Significant difference between treatments for the adjacent segment (1 segment above the index level; p=0.0008) and the level superior to that (2 segments above the index level: p=0.005).