Elbow taken as six handbreadths; three to the elbow and three from the elbow to the shoulder. Another measure was the "cubit" (from "cubital"). This was taken to be the length of a man's arm from the elbow to the end of the middle finger. Though the elbow is similarly adapted for stability through a wide range of pronation-supination and flexion-extension in all apes, there are some minor differences. In arboreal apes such as orangutans, the large forearm muscles originating on the epicondyles of the humerus generate significant transverse forces on the elbow joint. The structure to resist these forces is
Ulnar collateral ligament injury of the elbow and extension. The posterior oblique originates at the medial epicondyle and inserts along the mid-portion of the medial semilunar notch. It applies more stability against valgus stress when the elbow is flexed rather than extended. The transverse ligament connects to the inferior medial coronoid process of the ulna to the medial tip of the olecranon. Since it is connected to the same bone and not across the elbow joint, the transverse ligament has no contribution to the joint’s stability. In most cases, a physician will diagnose an ulnar collateral ligament injury using a patient’s medical history and a physical examination