pseudoboutonnière deformity

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pseudoboutonnière deformity

A finger posture marked by extension of the metacarpophalangeal and distal interphalangeal (DIP) joints and flexion of the proximal interphalangeal (PIP) joint. This condition outwardly resembles a boutonnière deformity. It can be diagnosed by performing the boutonnière deformity examination and asking the patient to flex the DIP joint extension of the PIP joint. If the patient cannot extend the PIP joint but can actively flex the DIP joint, a pseudoboutonnière deformity is indicated. See: boutonnière deformity


A rupture of the volar plate over the area of the proximal and middle phalanges causes the volar plate to displace dorsally relative to the PIP joint.


The finger is splinted with the PIP and DIP joints in extension. Surgery may be required for patients who do not respond to conservative treatment.

See also: deformity
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