1. Department of Orthopedic Surgery, Traumatology and Sports Medicine, Spital STS AG, Thun, Switzerland
2. Department of Surgical Sciences/Orthopedics and Hand Surgery, Uppsala University, Uppsala, Sweden
3. Elisabeth Hospital Aleris, Uppsala, Sweden
4. Centro Manoegomito, Gravesano, Switzerland
5. Department of Orthopedics, Falu Lasarett, Falun, Sweden