[1] Med Univ Vienna, Div Rheumatol, A-1090 Vienna, Austria
[2] Leiden Univ, Dept Rheumatol, Med Ctr, Leiden, Netherlands
[3] Univ Hosp La Paz, Madrid, Spain
[4] Copenhagen Univ Hosp Glostrup, Copenhagen Ctr Arthrit Res, Ctr Rheumatol & Spine Dis, Copenhagen, Denmark
[5] Ambroise Pare Hosp, Publ Hlth Dept, Boulogne, France
[6] Ambroise Pare Hosp, Dept Rheumatol, Boulogne, France
[7] Rheumazentrum Ruhrgebiet, Herne, Germany
[8] Copenhagen Univ Hosp Gentofte, Dept Rheumatol, Copenhagen, Denmark
[9] Aarhus Univ Hosp, Dept Radiol, DK-8000 Aarhus, Denmark
[10] Hosp Gen Univ Gregorio Maranon, Dept Rheumatol, Madrid, Spain
[11] Med Univ Vienna, Dept Biomed Imaging & Image Guided Therapy, Vienna, Austria
[12] King Christian 10th Hosp Rheumat Dis, Grasten, Denmark
[13] Karolinska Univ Hosp, Dept Radiol, Stockholm, Sweden
[14] Univ Politecn Marche, Dept Rheumatol, Ancona, Italy
[15] Univ Leeds, NIHR Leeds Musculoskeletal Biomed Res Unit, Leeds Inst Rheumat & Musculoskeletal Med, Leeds, W Yorkshire, England
[16] Charite, Dept Rheumatol, D-13353 Berlin, Germany
[17] Univ Erlangen Nurnberg, Dept Rheumatol & Immunol, D-91054 Erlangen, Germany
[18] Copenhagen Univ Hosp, Parker Inst, Dept Rheumatol, Musculoskeletal Stat Unit, Copenhagen, Denmark