[1] City Hosp Brandenburg, Dept Orthopaed & Traumatol, D-14770 Brandenburg, Germany
[2] Otto Von Guericke Univ, Dept Orthopaed, Magdeburg, Germany
[3] Hosp Waldfriede, Dept Traumatol & Hand Surg, Berlin, Germany
[4] StatConsult GmbH, Magdeburg, Germany