1. Department of Mechanical and Materials Engineering, McLaughlin Hall, Queen’s University, Kingston K7L 3N6, Canada.
2. Department of Orthopaedic Surgery, Hopital Cantonal Fribourg, Bertigney Strasse, 1700 Fribourg, Switzerland.
3. Institute of Pathology University of Bern, Murtenstrasse 31, 3010 Bern, Switzerland.