Shoulder joint involvement in patients with newly diagnosed rheumatoid arthritis. Prevalence and associations

To estimate the prevalence of reduced function, compared to normative values, and tenderness in the shoulder in patients with newly diagnosed rheumatoid arthritis (RA), and to investigate associated factors.

Eighty consecutive patients with RA, participating in a prospective study of early rheumatoid arthritis, were examined and assessed within one year of the onset of symptoms.

The prevalence of tenderness from any of the shoulder joints was 50%, while 30% had decreased shoulder function, compared with age matched controls, in at least one shoulder. Both tender shoulder joints and decreased shoulder function were related to higher age and more severe disease, reflected by disability (HAQ) and the patient's assessment of pain and global disease activity.

The shoulder girdle is involved early and often in rheumatoid arthritis and involvement is associated with a substantially more severe disease status. The study suggests that the shoulder should be given attention in patients with newly diagnosed rheumatoid arthritis, and that both tenderness and shoulder function should be evaluated.