1. Department of Orthopaedic Surgery, Federal University of São Paulo, São Paulo, Brazil
2. Department of Orthopaedic Surgery, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
3. Shiley Center for Orthopaedic Research and Education at Scripps Clinic, La Jolla, CA, USA
4. Division of Orthopaedic Surgery, Scripps Clinic, La Jolla, CA, USA