1. Department of Biomechanics, Hospital for Special Surgery, New York, NY, USA
2. Department of Foot and Ankle Surgery, Hospital for Special Surgery, New York, NY, USA
3. Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, USA
4. Department of Orthopaedic Surgery, Stanford University, Redwood City, CA, USA
5. Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA