1. Department of Trauma, Hand and Reconstructive Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building W1, 48149 Muenster, Germany
2. Research Group “Mathematical Surgery”, University Hospital Muenster, University of Muenster, 48149 Muenster, Germany
3. Institute of Biostatistics and Clinical Research, University of Muenster, Schmeddingstrasse 56, 48149 Muenster, Germany