1. Department of Orthopaedic Surgery; University Hospital of Tübingen; Tübingen Germany
2. Medical Faculty of the University of Tübingen; Tübingen Germany
3. G.E.R.N. Tissue Replacement, Regeneration & Neogenesis, Department of Orthopedics and Trauma Surgery; Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg; Freiburg Germany