Interphalangeal (IP) joint dislocations of the fingers and toes are common. Typically associated with forced hyperextension or hyperflexion of the digit, they require immediate reduction. The IP joint is a hinge joint that allows only flexion and extension and consists of several ligamentous complexes. The volar plate provides stability against hyperextension injury and dorsal dislocation of the phalanx. It often ruptures during a dorsal dislocation and may be associated with an avulsion fracture at the base of the phalanx. The strong collateral ligament complex resists hyperextension and lateral dislocation injury. The extensor hood complex stabilizes against hyperflexion injury and volar displacement of the phalanx.
Synonyms and related keywords: IP, finger, toe, proximal interphalangeal joint, PIP, distal interphalangeal joint, DIP, IP joint dislocations, interphalangeal joint dislocations, interphalangeal dislocations, toe dislocation, finger dislocation, dorsal PIP dislocation, volar IP dislocation, IP joint, PIP joint dislocations, DIP joint dislocations, thumb dislocation
Author: Grace M Young, MD 2008