1 Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada.
2 Division of Orthopaedic Surgery, Department of Surgery, McMaster University Medical Centre, Hamilton, Ontario, Canada.
3 Department of Orthopaedics, Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.; Department of Orthopaedics, Sahlgrenska University Hospital, Mölndal, Sweden.
4 Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.