[Development and forms of post-traumatic carpal instability]

Posttraumatic carpal instabilities may be caused either by fractures or by rupture of the ligaments and originate mostly from a sudden fall on the hand risen in defense. In this case forced dorsiflexion, supination and ulnarduction will be developed in the wrist joint and intracarpal region. The injury takes its course in four stages. According to the localisation we differ between radial carpal instabilities, which develop especially in the stages I and II, ulnar instabilities, which develop in the stages III and IV. Furthermore there exists a third kind of instability: the proximal carpal instability, which is localised in the radiocarpal joint. In addition to that we differ static and dynamic instabilities. For treatment in recent injuries the continuity of the ligaments and the shape and the size of the carpal bones are restored. In delayed cases it will be necessary to restore the ligaments by grafting, to perform intracarpal arthrodesis or osteotomy to correct the bony configuration.