1. Orthopedics and Rehabilitation, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA.
2. Department of Orthopedics, Hospital for Special Surgery, New York, New York, USA.
3. Department of Orthopaedics, Cleveland Clinic Foundation, Garfield Heights, Ohio, USA.
4. Department of Orthopaedics and Rehabilitation, Vanderbilt University Medical Center, Nashville, Tennessee, USA.