ANTERIOR DISLOCATION OF THE ULNA AT THE INFERIOR RADIO-ULNAR JOINT: Case Reports, with a Discussion of the Anatomy of Rotation of the Forearm

1. Two cases are reported of the uncommon condition of simple anterior dislocation of the head of the ulna at the inferior radio-ulnar joint. 2. The literature concerning the condition and its treatment is reviewed. 3. The mechanism of the inferior radio-ulnar joint is discussed with particular reference to the function of the triangular fibrocartilage. 4. The mechanism of injury is discussed and a new idea of this mechanism is put forward.