1. Department of Rehabilitation Medicine, University of Washington, Seattle, Washington, USA
2. Shriners Hospitals for Children–Boston, Boston, Massachusetts, USA
3. Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
4. Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Spaulding Research Institute, Harvard Medical School, Boston, Massachusetts, USA
5. Department of Surgery, University of Washington Harborview, Seattle, Washington, USA