[1] Karolinska Inst, Div Orthopaed & Biotechnol, Dept Clin Sci Intervent & Technol, Alfred Nobels Allee 8, S-14152 Huddinge, Sweden
[2] Karolinska Univ Hosp Huddinge, Dept Orthopaed, Stockholm, Sweden
[3] Karolinska Univ Hosp Solna, Karolinska Inst, Dept Women & Childrens Hlth, Elevhemmet H2 00, Stockholm, Sweden
[4] Northeastern Univ, Brigham & Womens Hosp, Dept Phys Therapy Movement & Rehabil Sci, Div Rheumatol Immunol & Allergy,Sect Clin Sci, Boston, MA 02115 USA
[5] Harvard Med Sch, Dept Med, Boston, MA 02115 USA
[6] Sophiahemmet Univ, Dept Nursing Sci, Stockholm, Sweden