Dislocation of the distal radioulnar joint: anatomy and clues to prompt diagnosis.

The articular disk is a strong, complex structure responsible for the stability of the distal radioulnar joint. It is injured by a hyperpronation or hypersupination injury which disrupts the disk or its strong central attachment to the ulna. Prompt diagnosis is essential for a good result as no good late reconstruction is available. Reliance on radiographs for the diagnosis will seldom be rewarding, and they are mainly of value in ruling out associated fractures. A careful clinical examination and a high index of suspicion are the best tools available for diagnosis in this injury.