1. Department of Orthopaedic Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, California
2. Department of Orthopaedics, Emory University School of Medicine, Atlanta, Georgia
3. Department of Orthopaedics, Dartmouth-Hitchcock Medical Center, Hanover, New Hampshire
4. Department of Orthopaedic Surgery, Northwestern University Feinberg School of Medicine, Chicago, Illinois