The medial antebrachial cutaneous nerve (MACN) is a branch of the brachial plexus with a great variation within its branches. Knowledge of these variations is critical to neurologists, hand surgeons, plastic surgeons, and vascular surgeons. The aim of this study was to search for variations of the MACN and to discuss their clinical significance. For this study, six arm cadavers from three fresh cadavers were dissected and examined to find and study possible anatomical variations of the MACN. The authors report a rare case of a variation of the MACN, in which there are four brachial cutaneous branches, before the separation to anterior (volar) and posterior (ulnar) branch, that provide sensory innervation to the medial, inferior half of the arm, in the area that is commonly innervated from the medial brachial cutaneous nerve. To our knowledge, this is the first documented case of this nerve variation. This variation should be taken into serious consideration for the differential diagnosis of patients with complaints of hypoesthesia, pain, and paresthesia and for the surgical operations in the medial part of the arm.
Keywords: Anatomical variations; clinical anatomy; medial antebrachial cutaneous nerve; medial cutaneous nerve of the forearm.