1. The Steadman Clinic, Vail, Colorado, USA.
2. Steadman Philippon Research Institute, Vail, Colorado, USA.
3. New England Patriots, Foxborough, Massachusetts, USA.
4. Department of Orthopaedic Surgery, Massachusetts General Hospital, Boston, Massachusetts, USA.
5. Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.