1. Department of Orthopaedics, Hadassah University Hospital, Hebrew University Medical School, Ein Kerem, PO Box 12000, Jerusalem, Israel.
2. Israeli Defence Forces, Medical Corps, Israel Military POB 02149, Israel.
3. Department of Orthopaedics, Huddinge University Hospital, Huddinge, S-14186, Sweden.
4. Department of Anatomy and Orthopaedics, Indiana University Medical Centre, Indianapolis, Indiana 46227, USA.