Jaccoud arthropathy

(A) Ulnar deviation, metacarpophalangeal subluxation, and swan-neck deformities are present. There is also diffuse soft-tissue swelling.
(B) A radiograph shows the deformities, but there is no true joint space narrowing or erosion, which would be expected in a patient with rheumatoid arthritis with similar hand deformities. This type of deformity in systemic lupus erythematosus is reducible and is caused by tendon laxity, rather than bony destruction, and may also be seen in post-rheumatic fever arthritis.