A boutonierre deformity may be seen in patients with rheumatoid arthritis. It describes a finger that is held in flexion at the proximal interphalangeal joint and in slight hyperextension at the distal interphalangeal joint.
It results from disruption of the central slip of the extensor. The lateral slips gradually separate and the proximal phalanx slips through the gap.
A boutonniere deformity may also develop as a result of trauma and in such cases, is often correctible. That seen in rheumatoid arthritis is usually incorrectible.
Last reviewed 01/2018