1. Department of Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
2. Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
3. Spaulding Rehabilitation Hospital, Spaulding Research Institute, Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, Massachusetts, USA
4. Department of Occupational and Physical Therapy, Shriners Hospital for Children, Northern California, University of California, Davis, USA
5. Department of Physical Medicine and Rehabilitation, University of Texas Southwestern, Dallas, USA