A Stab Wound to the Axilla Illustrating the Importance of Brachial Plexus Anatomy in an Emergency Context: a Case Report

BACKGROUND:Although open injuries involving the brachial plexus are relatively uncommon, they can lead to permanent disability and even be life threatening if accompanied by vascular damage. We present a case report of a brachial plexus injury in which the urgency of the situation precluded the use of any ancillary diagnostic examinations and forced a rapid clinical assessment. CASE PRESENTATION: We report a case of a Portuguese man who had a stabbing injury at the base of his left axilla. On observation in our emergency room an acute venous type of bleeding was present at the wound site and, as a result of refractory hypotension after initial management with fluids administered intravenously, he was immediately carried to our operating room. During the course of transportation, we observed that he presented hypoesthesia of the medial aspect of his arm and forearm, as well as of the ulnar side of his hand and of the palmar aspect of the last three digits and of the dorsal aspect of the last two digits. Moreover, he was not able to actively flex the joints of his middle, ring, and small fingers or to adduct or abduct all fingers. Exclusively relying on our anatomical knowledge of the axillary region, the site of the stabbing wound, and the physical neurologic examination, we were able to unequivocally pinpoint the place of the injury between the anterior division of the lower trunk of his brachial plexus and the proximal portion of the following nerves: ulnar, medial cutaneous of his arm and forearm, and the medial aspect of his median nerve. Surgery revealed a longitudinal laceration of the posterior aspect of his axillary vein, and confirmed a complete section of his ulnar nerve, his medial brachial and antebrachial cutaneous nerves, and an incomplete section of the ulnar aspect of his median nerve. All structures were repaired microsurgically. Three years after the surgery he showed a good functional outcome. CONCLUSIONS: We believe that this case report illustrates the relevance of a sound anatomical knowledge of the brachial plexus in an emergency setting.