1 Department of Orthopaedic Surgery, UPMC Freddie Fu Sports Medicine Center, University of Pittsburgh, 3200 S. Water St, Pittsburgh, PA, 15203, USA.
2 Department for Orthopaedic Sports Medicine, Klinikum Rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany.
3 Department of Physical Therapy, University of Pittsburgh School of Health and Rehabilitation Sciences, Suite 210, 100 Technology Drive, Pittsburgh, PA, 15219, USA.
4 Department for Orthopaedics, Sahlgrenska University Hospital, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden.
5 Department of Orthopaedic Surgery, UPMC Freddie Fu Sports Medicine Center, University of Pittsburgh, 3200 S. Water St, Pittsburgh, PA, 15203, USA. musahlv@upmc.edu.