ULNA
Updated 04-May-2020.
Mondo shtuff from around the internet, all about ULNA!
Definition of ULNA: the bone on the little-finger side of the human forearm; also : a corresponding part of the forelimb of vertebrates above fishes… See the full definition
My botty best at summarizing from Wikipedia: the ulna is a long bone found in the forearm that stretches from the elbow to the smallest finger . it runs parallel to the radius and narrows as it approaches the wrist . close to the elbow close to the wrist, the ulna has a styloid process . the olecranon is a large, thick, curved eminence . posterior surface is triangular, smooth, subcutaneous, and covered by a bursa . its anterior surface is smooth, concave, and forms the upper part of the semilunar notch . the coronoid process is a triangular eminence projecting forward from the ulna . its apex is pointed, slightly curved upward, and in flexion of the forearm the flexor pollicis longus arises from the lower part of the coronoid process by a rounded bundle of muscular fibers . a small rounded eminence for the origin of one head the semilunar notch is a large depression formed by the olecranon and the coronoid process . about the middle of either side is an indentation, which contracts it somewhat . the it tapers gradually from above downward, and has three borders and three surfaces . it is concave from before backward, and its prominent extremities serve for the attachment of the annular ligament . dorsal border is well-marked in the upper three-fourths . it gives attachment to an aponeurosis . the lower fourth is separated from the remaining portion by a ridge . at the junction of the upper and middle third of the bone is the nutrient canal . the medial part is smooth, and covered by the exten the head of the ulna is a rounded, articular eminence near the wrist . the head is separated from the styloid process by a depression . the long, narrow medullary cavity of the ulna is enclosed in a strong wall of cortical tissue . at the extremities the compact layer thins . trabecul arch forward toward the the trabecul at the lower end have a more longitudinal direction . at birth, the ends are cartilaginous . about the fourth year, a center appears in the middle of the head . the upper epiphysis joins the body about the sixteenth, the lower about the twentieth year . the ulna joins (articulates) with: trochlea of the humerus, at the ulna is partially or wholly fused with the radius, and may not exist as a separate bone . but even in extreme cases of fusion, such as in horses, the olecranon process