72.17 Fractures of the olecranon

A patient can fracture his olecranon in two ways: (1) He can receive a direct blow to the point of his elbow which fractures it directly. (2) He can fall on his outstretched hand at the same time as his triceps is contracting, and thus break his olecranon indirectly. In both cases his elbow is acutely tender and swollen. Sometimes the head of his radius is also injured.

Examine him. Can he extend his forearm against gravity, as in A, Fig. 72-24?

Figure 72.24: CONSERVATIVE TREATMENT FOR AN OLECRANON FRACTURE. A, testing a patient’s triceps mechanism by seeing if he can extend his elbow against gravity. B, early active movements with his arm in a sling gave this patient enough power to lift this heavy book, with only a little loss of extension. C, shows the extensive comminution of his olecranon. D, If a patient has lost his triceps mechanism and has move than half his olecranon fossa intact, excise the proximal fragment and sew his triceps tendon to his ulna. If less than half is intact use tension band wiring. Kindly contributed by Peter Bewes and John Stewart.

If he can extend his arm against gravity, the extensor mechanism of his s elbow is intact, and active movements alone are enough, whatever his X–ray may show.

If he cannot extend his forearm against gravity, his extensor mechanism needs repair. Look at his lateral X–ray. If more than half his olecranon fossa is intact, excise the proximal fragments and suture his triceps to his ulna, as in Fig. 72-24. If less than half his olecranon fossa is intact, fix the two fragments of his olecranon by tension band wiring (Fig. 72-27). In this method two stiff Kirschner wires go obliquely through his olecranon and are anchored in the cortical bone of the anterior surface of his ulna to give the fragment longitudinal stability. They are kept together by a band of flexible steel wire, wound in a figure of eight. If you don’t have the equipment for tension band wiring, or if a patient’s olecranon is in many fragments, you can excise the fragments and suture his triceps to his ulna.

If his elbow needs repair, but this is not possible, treat him with active movements, and warn him to expect some permanent loss of extension.

Olecranon injuries in children.

A child may have several centres of ossification in his olecranon, so you may have difficulty deciding if he has a fracture or not. If in doubt, X–ray his other elbow. The epiphysis of the olecranon occasionally separates from the shaft of the ulna between the ages of 10 and 16. If it does, treat it in the same way as you would a fracture.