Instability of the metacarpophalangeal joint of the thumb. Reconstruction of the collateral ligaments using the extensor pollicis brevis tendon.

Reconstruction of the collateral ligaments of the metacarpophalangeal joint of the thumb was performed for fourteen ruptures of the ulnar and two ruptures of the radial collateral ligament, one to eighteen months after injury. The extensor pollicis brevis tendon was used to reinforce the resutured ligament. Symptoms were relieved in all cases after follow-ups ranging from one to seven years, even in two thumbs with mild degenerative arthritis of the metacarpophalangeal joint.