Capitulum of the humerus the distal end. In non-avian archosaurs, including crocodiles, the capitellum and the trochlea are no longer bordered by distinct etc.- and entepicondyles respectively, and the distal humerus consists two gently expanded condyles, one lateral and one medial, separated by a shallow groove and a supinator process. Romer (1976) homologizes the capitellum in Archosauromorphs with the groove separating the medial and lateral condyles. In birds, where forelimb anatomy has an adaptation for flight, its functional if not ontogenetic equivalent is the dorsal condyle of the humerus. Capitulum of the humerus In human anatomy of the arm, the capitulum of the humerus
Radius (bone) Radius (bone) The radius or radial bone is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The radius is shorter and smaller than the ulna. It is a long bone, prism-shaped and slightly curved longitudinally. The radius is part of two joints: the elbow and the wrist. At the elbow, it joins with the capitulum of the humerus, and in a separate region, with the ulna at the radial notch. At the