Martin-Gruber anastomosis

Martin-Gruber anastomosis is the most common type of four inter neural communication between median nerve and ulnar nerve in forearm and hand. Its prevalance has been reported between 11- 27%. Motor fibers from median, most commonly from anterior interosseous nerve cross to join ulnar nerve. Motor fibers may pass via ulnar nerve and innervate the muscles of hand, confounding clinical assessment and EMG interpretations in patients with carpal tunnel syndrome.