1. Department of Orthopaedic Surgery, Johns Hopkins Medical Institutions, Baltimore, Maryland
2. Plastic and Reconstructive Surgery, Charité-Universitätsmedizin Berlin, Germany
3. Department of Plastic and Hand Surgery, University of Freiburg Medical Centre, Freiburg, Germany
4. Department of Plastic, Aesthetic and Hand Surgery, Otto von Guericke University, Magdeburg, Germany