Asymmetry in Rheumatoid Arthritis

While the common teaching is of rheumatoid arthritis as a symmetric process, asymmetric involvement can be seen in about 15% of cases. The tendency is toward symmetrization with time, and seropositive patients are more than twice as likely to eventually have symmetric involvement compared to seronegative patients.

Asymmetric involvement is more commonly seen at the metacarpophalangeal joints and at the wrist. The case above is a somewhat extreme example in a patient with positive rheumatoid factor. There are advanced findings of rheumatoid arthritis centered at the right wrist without significant abnormality in the other joints or on the left side.

References

• Clarke GS, Buckland-Wright JC, Grahame R. Symmetry of radiological features in the wrist and hands of patients with early to moderate rheumatoid arthritis: a quantitative microfocal radiographic study. Br J Rheumatol. 1994 Mar;33(3):249-54.
• Zangger P, Keystone EC, Bogoch ER. Asymmetry of small joint involvement in rheumatoid arthritis: prevalence and tendency towards symmetry over time. Joint Bone Spine. 2005 May;72(3):241-7.