[1] Kerckhoff Klin, Bad Nauheim, Germany
[2] Univ Marburg, Dept Rheumatol & Clin Immunol, D-35032 Marburg, Germany
[3] Univ Giessen, Dept Rheumatol & Clin Immunol, D-35390 Giessen, Germany
[4] Univ Giessen, Dept Orthoped & Orthoped Surg, D-35390 Giessen, Germany
[5] Univ Marburg, Dept Orthoped & Orthoped Surg, D-35032 Marburg, Germany
[6] Univ Marburg, Dept Orthoped & Exp Orthoped, D-35032 Marburg, Germany
[7] Univ Giessen, Dept Orthoped & Exp Orthoped, D-35390 Giessen, Germany
[8] USZ, Ctr Exp Rheumatol, Zurich, Switzerland