1. Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, Illinois, USA
2. Department of Orthopaedic Surgery, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, USA
3. Department of Orthopaedic Surgery, University of California San Francisco Medical Center, San Francisco, California, USA
4. Department of Internal Medicine, Rush University Medical Center, Chicago, Illinois, USA
5. Department of Orthopaedic Surgery, University of Nebraska Medical Center, Omaha, Nebraska, USA
6. Division of Adult Reconstruction, Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, Illinois, USA