Degenerative diseases of the metacarpophalangeal joints.

Degenerative arthritis of the finger metacarpophalangeal joints is uncommon and, when seen, a specific etiology should be sought. MP joint arthritis in the absence of a history of trauma may signal an underlying systemic disease. The clinical and radiographic findings may be subtle. Once degenerative changes occur, the usual treatment is arthroplasty using a flexible silicone rubber (Swanson) finger joint implant that should provide a relatively stable and painless joint with a functional range of motion. Degenerative arthritis of the thumb MP joint is more common following injuries that damage the ligaments on the ulnar or radial side of the MP joint and which result in lateral instability of the joint. Arthritis of the MP joint also may occur following infection or direct joint injury. Secondary MP arthritis may result from thumb CMC joint disease and must be attended to at the time CMC joint reconstruction is performed. Degenerative disease of the thumb sesamoid bones must be considered in patients with persistent MP joint pain after either trauma or MP joint fusion.