Location of ulnar nerve

The ulnar nerve is a large branch of the medial cord. It splits from the medial cord in the shoulder, and descends along the medial aspect of the arm, passes under the medial epicondyleof the humerus and then along the forearm between flexor carpi ulnaris and flexor digitorum profundus. It then enters the hand, where it supplies most of its muscles and skin with innervation. It is also responsible for the sensation when you "hit your funny bone"; the nerve is squashed on the medial epicondyle.