1. Department of Orthopaedic Sports Medicine and Arthroscopic Surgery, Rennbahnklinik Muttenz, Basel, Germany
2. Department of Orthopaedic Sports Medicine and Arthroscopic Surgery, Hessing Stiftung Augsburg, Augsburg, Germany
3. Department of Orthopaedic Surgery, University Hospital Basel, Basel, Switzerland
4. Department of Orthopaedic Surgery, Hospital Oberengadin, Samedan, Switzerland