Ulna, fracture of

A fracture of the ulna, 1 of the 2 bones of the forearm. Ulnar fractures typically occur across the shaft or at the olecranon process. A fracture to the shaft usually results from a blow to the forearm or a fall onto the hand. Sometimes the radius is fractured at the same time (see radius, fracture of). Surgery is usually needed to reposition the broken bone ends and fix them together using either a plate and screws or a long nail down the centre of the bone. The arm is immobilized in a cast, with the elbow at a rightangle, until the fracture heals. A fracture of the olecranon process is usually the result of a fall onto the elbow. If the bone ends are not displaced, the arm is immobilized in a cast that holds the elbow at a rightangle. If the bone ends are displaced, however, they are fitted together and fixed with a metal screw.