<P> The bone may break due to excessive weight or impact . </P> <P> The ulna is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm . It is broader close to the elbow, and narrows as it approaches the wrist . </P> <P> Close to the elbow, the ulna has a bony process, the olecranon process, a hook - like structure that fits into the olecranon fossa of the humerus . This prevents hyperextension and forms a hinge joint with the trochlea of the humerus . There is also a radial notch for the head of the radius, and the ulnar tuberosity to which muscles attach . </P> <P> Close to the wrist, the ulna has a styloid process . </P>

Where does the ulna articulate with the humerus