1. David Geffen School of Medicine at UCLA, Los Angeles, California, USA
2. Knee Division, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina
3. Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
4. Pediatric Orthopedic Surgery Service, Hospital for Special Surgery, New York, New York, USA
5. Stanford University, Stanford, California, USA
6. Department of Orthopaedic Surgery, Division of Sports Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, USA