The Fractures of the Olecranon

Abstract

The subcutaneous location of the olecranon makes it vulnerable to trauma [1]. Isolated fractures of the olecranon comprise approximately 10% of fractures about the elbow [2, 3], with an estimated incidence of 1.08 per 10,000 person-years [3]. Most result from low energy trauma such as a fall from a height of less than 2 m, a direct blow to the elbow, or from forced hyperextension [2–7]. A fall on a partially flexed elbow may generate an avulsion fracture of the olecranon from the pull of the triceps [1]. Amis et al. [7] investigated variable impact mechanisms and the resultant fracture patterns in a cadaveric model. A trend was noted in which radial head and coronoid fractures tended to occur with forearm impacts with the elbow in up to 8o° of flexion [7]. Olecranon fractures occurred with direct blows at 90° of flexion, while injuries occurring with the elbow in > 110° of flexion tended to result in distal humerus fractures [7].