1. Department of Orthopedic Surgery, University of Colorado School of Medicine, 12631 East 17th Avenue, B202, Aurora, CO 80045, USA
2. Cedars-Sinai Medical Center, Los Angeles, CA, USA
3. Washington University School of Medicine, MO, USA
4. Kantonspital Baselland, Liestal, Switzerland
5. University of Washington, Seattle, WA, USA
6. Hospital for Special Surgery, New York, NY, USA
7. Mercy Medical Center, Baltimore, MD, USA
8. New York University Grossman School of Medicine, New York, NY, USA
9. Johns Hopkins School of Medicine, Baltimore, MD, USA
10. Georgetown School of Medicine, Washington, DC, USA
11. Department of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA, USA