flexion and extension at the elbow. Maximum elbow flexion and extension is made possible because the two fossae accommodates to coronoid and olecranon processes. Ossification While the ossification of the capitulum has started a year after birth, the ossification of the trochlea begins at 8–9 years of age; that of the head of radius and the medial epicondyle at 4–5 years and that of the lateral condyle at 10 years. Additional images References External links Bones of the upper limb Humerus