1. University of Pennsylvania, Department
of Orthopaedic Surgery, 800 Spruce Street, 8th
Floor Preston Building, Philadelphia, Pennsylvania
19107, USA
2. Hospital of the University of Pennsylvania, Department
of Orthopaedic Surgery, 3400 Spruce Street, 2
Silverstein, Philadelphia, 19104, USA
3. Rush University, Midwest Orthopaedics, 1655
West Harrison Street, Chicago, Illinois 60612, USA