Thumb reconstruction by the posterior interosseous osteocutaneous flap.

An island osteo-fasciocutaneous flap, based on the posterior interosseous vessels, is described for thumb reconstruction. The artery supplies the fascial plexus of the posterior forearm as well as the superficial and deep extensor muscles. A vascularised bone segment of the upper third of the ulna can be harvested, including a cuff of the extensor pollicis longus muscle. The flap was used successfully in two clinical cases.