1. Department of Orthopaedic Surgery, Park Nicollet Methodist Hospital, St. Louis Park, MN, USA
2. Department of Orthopaedic Surgery, TRIA Orthopaedic Institute, Bloomington, MN, USA
3. Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, MN, USA
4. Department of Orthopaedic Surgery, Denver Health Medical Center, University of Colorado, Denver, CO, USA