1 Department of Orthopaedic Surgery, UPMC Freddie Fu Sports Medicine Center, University of Pittsburgh, Pittsburgh, PA, USA.
2 Department of Orthopaedic Sports Medicine, Klinikum Rechts Der Isar, Technical University Munich, Munich, Germany.
3 Division of Orthopaedic Surgery, Department of Surgery, McMaster University, Hamilton, ON, Canada.
4 Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. jon.karlsson@vgregion.se.