Fracture of the coronoid process is rare except as a complication of backward dislocation of the elbow. It may be produced by direct violence, as well as by muscular action. As the fracture is usually within a quarter of an inch of the tip, the fibres of insertion of the brachialis prevent displacement. The ordinary evidence of fracture is often absent, and the diagnosis is seldom completed without the aid of the X-rays. The treatment consists in flexing the elbow and supporting the forearm in a sling. In some cases associated with dislocation, however, the small fragment has been so far displaced as to become attached to the back of the humerus (Annandale).
Fracture of the Upper End of the Radius
Intra-capsular fracture of the head of the radius may result from direct violence, from a fall on the pronated hand, or from forcible pronation or abduction—that is, deviation of the forearm to the radial side. It may accompany dislocation of the elbow or fracture of adjacent bones. The head may be completely separated, or may be split into two or more fragments. Up to the seventeenth year, the epiphysis, which is entirely intra-articular, may be separated.
The clinical features are localised pain, crepitus, interference with pronation and supination, while the elbow can be almost fully extended and flexed, and in some cases the fragment may be felt through the skin, although it usually continues to move with the shaft in pronation and supination.
Union generally takes place satisfactorily, but in some cases the fragments form new attachments resulting in impaired movement at the elbow, and necessitating operative interference.
Fracture of the neck of the radius between the capsule and the tubercle is rare.
Avulsion of the tubercle may occur from forcible contraction of the biceps, or, in children, from traction made on the forearm (A. L. Hall).
These injuries are treated with the elbow in the flexed position, and massage and movement are carried out as already described.
Dislocation of the Elbow
Dislocations of the elbow-joint may involve one or both bones of the forearm, and may be complete or incomplete.