1. Department of Orthopedic Surgery, Inselspital, University of Bern, Bern, Switzerland
2. Department of Diagnostic, Interventional and Pediatric Radiology, University Hospital and University of Bern, Bern, Switzerland
3. Department of Orthopedic Surgery, Universitätsklinikum St. Pölten, Sankt Pölten, Austria
4. University of Bern, Bern, Switzerland