[1] Univ Duisburg Essen, Dept Orthopaed & Trauma Surg, Hufelandstr 55, D-45147 Essen, Germany
[2] Univ Duisburg Essen, Klin Orthopadie Unfall & Wiederherstellungschirur, St Marienhosp Mulhe, Contilia Grp, Essen, Germany
[3] Univ Saarland, Dept Orthopaed, Saarbrucken, Germany
[4] Hannover Med Sch, Klin Orthopadie, Diakovere Annastift, Hannover, Germany
[5] Univ Halle, Klin Orthopadie & Unfallchirurg, Halle, Germany
[6] Ruhr Univ Bochum, Kathol Klinikum Bochum, Orthopadie & Unfallchirurg, Bochum, Germany
[7] Marienhaus Klinikum St Josef, Klin Orthopadie, Bendorf, Germany
[8] Elisabeth Klin, Orthopadie Unfall Hand & Wiederherstellungschirug, Bigge Olsberg, Germany