William B. Morrison, MD, Professor of Radiology, Past President, Society of Skeletal Radiology, Director, Division of Musculoskeletal Radiology, Thomas Jefferson University Hospital and Rothman Institute, Philadelphia, PA, USAJohn A. Carrino, MD, MPH, Professor and Vice Chair of Radiology, Hospital for Special Surgery, New York, NY, USA Adam E. Flanders, MD, Professor of Radiology, Past President, American Society of Spine Radiology, Co-Director, Division of Neuroradiology, Thomas Jefferson University Hospital, Philadelphia, PA, USA