1 R. E. Marcus, Charles H. Herndon Professor and Chairman, Department of Orthopaedics, Case Western Reserve University, University Hospitals Cleveland Medical Center, Cleveland, OH, USA C. L. Barnes, Carl L. Nelson Distinguished Chair, Department of Orthopaedic Surgery, University of Arkansas for Medical Sciences, Little Rock, AR, USA A. Amendola, Vice Chair, Department of Orthopedic Surgery, and Chief, Division of Sports Medicine, Duke University, Durham, NC, USA.