1 Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland (Bruderholz, Liestal, Laufen), 4101, Bruderholz, Switzerland. michael.hirschmann@ksbl.ch.
2 University of Basel, 4000, Basel, Switzerland. michael.hirschmann@ksbl.ch.
3 Department of Orthopedics and Traumatology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands.
4 Department of Orthopedics and Traumatology, Centre of Joint Replacement, Hospital Brandenburg and "Theodor Fontane" Medical School, 14770, Brandenburg/Havel, Germany.