1. Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, California
2. Institute for Global Orthopaedics and Traumatology, Department of Orthopaedic Surgery, University of California San Francisco School of Medicine, San Francisco, California
3. Surgical Implant Generation Network (SIGN), Richland, Washington
4. Department of Medicine Statistics Core, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.