[1] Department of Rheumatology,
[2] Physical Medicine and Rehabilitation,undefined
[3] Hôpital Cantonal,undefined
[4] 1708 Fribourg,undefined
[5] Switzerland e-mail: balaguef@etatfr.ch,undefined
[6] Fax: 41-26-426 73 87,undefined
[7] Department of Rheumatology,undefined
[8] University Hospital of Grenoble,undefined
[9] France,undefined
[10] Department of Physical Medicine and Rehabilitation,undefined
[11] University Hospital of Turku,undefined
[12] Finland,undefined