Successful treatment of the pain related to medial humeral epicondyle remains illusive. A possible explanation of the etiology of the pain is that the innervation of medial epicondyle suffers repeated stretch/traction injuries, and that the pain is neural in origin. The other one is that innervation to the medial epicondyle is not well defined, nor at present time, an operative approach for its denervation exists. Therefore, the purpose of the present study was to identify the innervation of the medial epicondyle of the humerus. Incidentally, over the past several years, we noted a group of patients presenting with cubital tunnel syndrome, which also had pain the region of the medial epicondyle that would intensify by resisted elbow flexion. Postoperatively, after they underwent submuscular ulnar nerve transposition, described by Dellon, that pain would disappear. In order to explain this observation, we started to submit a peace of the medial intermuscular septum (MIMS) to pathology that in consecutive 8-10 cases identified the presence of a nerve. We dissected 10 arms in five fresh cadavers and studied the innervation of the medial epicondyle. Dissections with loupe magnification were done in order to evaluate the origin and variability of nerves in this region. We identified a consisted medial epicondyle innervation with a nerve that was present in the MIMS. When dissected more proximally, the nerve was present in tight proximity to the ulnar nerve. When the nerve was followed more proximally, it was found to have an origin from radial, rather then ulnar nerve. It leaves the radial nerve at the level of the anterior axillary line and descends along the ulnar nerve to innervate medial epicondyle via intermuscular septum. As it descended, it gave in the distal third of the upper arm, in addition to MIMS branch, 1-3 small branches to medial triceps muscle. In 7 specimens, it was the only branch from radial nerve, while in 3 specimens, it also received a contribution from ulnar nerve (also in the axilla) and then continued distally. This report, for the first time identifies a nerve innervating the medial epicondyle via MIMS. Resection of MIMS with ulnar nerve transposition, relieved epicondylar pain in these patients, and could also be used in patients with medial epicondylar pain due to sports related injuries.