1. Department of Orthopaedic Surgery, Schulthess Clinic, Lengghalde 2, 8008 Zurich, Switzerland.
2. Department of Radiology
3. Department of Orthopaedic Surgery, Kantonsspital Chur, Loestrasse 170, 7000 Chur, Switzerland.
4. Department of Orthopaedics, University of Duisburg-Essen, Pattbergstrasse 1-3, 45239 Essen, Germany.