Ulnar nerve passes under a groove between medial epicondyl and olecranon in order to pass between two heads of flexor carpi ulnaris under the fasial band (cubital tunnel) that combines the two heads. Entrapment in the elbow or just distal site of the elbow causes a rare syndrome called “cubital tunnel syndrome”. Pain in the inner side of elbow is typical in this syndrome. Muscles in the forearm and flexor muscles of the third and fourth fingers are weakened. It may be difficult to do differential diagnosis with C8 and T1 radiculopathy. Clinical sensitivity, pain of inner elbow and EMG helps doing differential diagnosis. Treatment is surgical. Nerve is operated with microsurgical techniques.

 Guyon’s Canal Syndrome

Terminal ulnar nerve enters in “Guyon’s canal”, which is made by palmar fasia and Palmaris brevis on the top, retinaculum and pisohamate ligament on the bottom. There are no tendons in this canal. Only ulnar nerve and artery are present. The nerve divides into two branches in the middle of the canal; superficial one is more a sense nerve, deep one is a motor nerve. Other ulnar nerve entrapment signs are present, apart from that there is no loss of sense in the dorsal hand. It may be confused with C( and T1 radiculopathy. T1 muscles are normal, which are innervated from the median nerve. Electrodiagnostic tests may be useful for locating the lesion.