Olecranon

The olecranon /oʊˈlɛkrənɒn/ from the Greek olene meaning elbow and kranon meaning head is the large, thick, curved bony eminence of the ulna, a long bone in the forearm that projects behind the elbow. It forms the most pointed portion of the elbow and is opposite to the cubital fossa or elbow pit. The olecranon serves as a lever for the extensor muscles that straighten the elbow joint.Upper extremity of left ulna. Lateral aspectBones of left forearm. Anterior aspect.Plan of ossification of the ulna. From three centers.Left elbow-joint, showing anterior and ulnar collateral ligaments.Capsule of elbow-joint (distended). Posterior aspect. The olecranon /oʊˈlɛkrənɒn/ from the Greek olene meaning elbow and kranon meaning head is the large, thick, curved bony eminence of the ulna, a long bone in the forearm that projects behind the elbow. It forms the most pointed portion of the elbow and is opposite to the cubital fossa or elbow pit. The olecranon serves as a lever for the extensor muscles that straighten the elbow joint. It is situated at the upper (proximal) end of the ulna, one of the two bones in the forearm. When the hand faces forward (supination) the olecranon faces towards the back (posteriorly). It is bent forward at the summit so as to present a prominent lip which is received into the olecranon fossa of the humerus in extension of the forearm.