72.4 Dislocation of the elbow

A patient of any age can dislocate his elbow if he falls on his outstretched hand. In this common injury a force travels up his forearm and pushes his radius and ulna posteriorly, or his humerus posteriorly and laterally. He cannot move his elbow, and holds it at about 45. The posterior outline of his arm, instead of being normally rounded, or showing a slight prominence over his olecranon, bends abruptly backwards as in C, Fig. 72-2. The three bony points of the elbow are not in their normal places. There may be other injuries also: (1) A child may fracture his medial epicondyle which may become trapped inside his dislocated elbow. (2) His lateral condyle may also fracture.

A patient may also have severe soft tissue injuries, and occasionally the circulation of his forearm is obstructed, with the danger of Volkmann’s ischaemic contracture (70.4).