1. Seattle Science Foundation, Seattle, Washington, USA
2. Western University of Health Sciences, College of Osteopathic Medicine of the Pacific-Northwest, 200 Mullins Dr., OR 97355, Lebanon
3. University of Illinois College of Medicine, 1835 W Polk St., Chicago, IL 60612, USA
4. Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA
5. Department of Trauma Surgery, BG University Hospital Bergmannsheil, Ruhr University Bochum, Bochum, Germany
6. Hansjörg Wyss Hip and Pelvic Center, Swedish Hospital, Seattle, Washington, USA