1. Hansjörg Wyss Hip and Pelvic Center, Swedish Hospital, 600 Broadway #340, Seattle, WA 98122, USA
2. Swedish Neuroscience Institute, Swedish Medical Center, 550 17th Ave #540, Seattle, WA 98122, USA
3. Seattle Science Foundation, 550 17th Ave Suite 600, Seattle, WA 98122, USA
4. Department of Trauma Surgery, BG University Hospital Bergmannsheil, Ruhr University Bochum, Bürkle-de-la-Camp-Platz 1, Bochum 44789, Germany