The ulnar nerve arises from the medial cord of the brachial plexus in common with the medial head of the median. It lies upon the medial side of the third portion of the axillary artery, between it and the axillary vein. It then passes down the medial side of the arm upon the medial surface of the triceps, piercing the medial intermuscular septum together with the superior ulnar collateral artery at the distal third of the arm to reach the space between the medial epicondyle and the olecranon.

Nervus ulnaris

Nerf ulnaire