1. Department of Radiology; Medical University of Vienna; Lazarettgasse 14 1090 Vienna Austria
2. Department of Trauma Surgery; University of Erlangen; Krankenhausstrasse 12 91054 Erlangen Germany
3. Department of Orthopaedic Surgery, Inselspital; University of Berne; Freiburgstrasse 3010 Berne Switzerland
4. Institute of Electronics; Technical University of Lodz; Wolczanska 211/213 90924 Lodz Poland
5. Department of Radiology; University Medical Center Utrecht; Heidelberglaan 100, E01.132 3584 CX Utrecht The Netherlands