1. Department of Plastic Surgery, University Medical Center Regensburg, Germany
2. Applied Stem Cell Research Center, University Medical Center Regensburg, Germany
3. Department of Trauma Surgery, University Medical Center Regensburg, Germany
4. Department of Obstetrics and Gynecology, University Medical Center Regensburg, Regensburg, Germany
5. Department of Orthopaedics and Trauma Surgery, University Hospital Basel, Switzerland