[1] Jyvaskyla Cent Hosp, Dept Phys & Rehabil Med, Jyvaskyla 40620, Finland
[2] Jyvaskyla Cent Hosp, Dept Surg, Jyvaskyla 40620, Finland
[3] Univ Helsinki, Dept Orthoped & Traumatol, Helsinki, Finland
[4] Helsinki Univ Hosp, Helsinki, Finland
[5] Univ Helsinki, Cent Hosp, Unit Primary Hlth Care, Helsinki, Finland
[6] Univ Helsinki, Dept Gen Practice, Helsinki, Finland
[7] Univ Jyvaskyla, Dept Hlth Sci, Jyvaskyla, Finland