X-ray diagnosis, treatment and prognosis of radioulnar subluxation.

There is no uniform classification standard for injuries of the lower radioulnar joint. It can be divided into three types: type ⅰ: potential instability: fracture displacement of styloid process base of ulna, radial ulnar notch or radial ulnar joint surface displacement fracture, angular fracture of radius and overlapping displacement deformity. Type ⅱ: subluxation: the ratio of the gap between the lower radioulnar joint and the opposite joint is widened by 0.5-2.0.

Cm and CT films were diagnosed as subluxation by MINO method. Type Ⅲ: Dislocation: the ulnar capitulum is obviously higher than the contralateral one, and the space of the lower radioulnar joint is wider than the contralateral one >: 2cm.

MINO CT showed dislocation.

There are four other types: type I: clinical symptoms, mainly positive compression test of lower radioulnar joint, and no separation was found on X-ray film. Type ⅱ: In addition to the above clinical symptoms, X-ray film showed that the lateral part of the lower radioulnar joint was separated from the main trunk 2.

Cm type ⅲ: apart from type ⅱ, there are palmar dorsal separation and ulnar capitulum moving backward >: 1/4. In some cases, snap sign of the lower radioulnar joint appears. Ⅳ

Type: separation of lower radioulnar joint with complications. Because volar dislocation is less common than dorsal dislocation, volar dislocation is not included in the above classification method.