Boutonniere Deformity

On examination, joint swelling may be visible or may be apparent only by palpation. The tissue feels soft and spongy and may appear erythematous and warm, especially early in the course of the disease. Chronic joint deformities commonly involve subluxations of the wrists, metacarpophalangeal joints, and proximal interphalangeal joints (swan-neck deformity, boutonniere deformity, ulnar deviation). 

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