Entrapment of subscapular artery by the splitting of radial nerve- putative clinical implications.

The third part of the axillary artery has an intimate relationship with the cords of the brachial plexus. The subscapular artery, the largest branch of the axillary artery, arises from its third part. The radial nerve is a branch of the posterior cord of the brachial plexus and its supplies the extensors of the arm, forearm and dorsum of the hand. During routine undergraduate dissection of the axilla of a formalin-fixed cadaver of about 70 years, the subscapular artery was found sandwiched between two divisions of the radial nerve. These anterior and posterior divisions of the radial nerve arose immediately after the formation of the radial nerve and encircled the subscapular artery and fused to form a single nerve subsequently. This variant anatomy can lead to conditions like subscapular entrapment causing ischemia of the scapular region and radial nerve compression causing weakness of the extensors of the upper limb. Injury to the nerve and vessel can occur while performing diagnostic and therapeutic procedures in the area. Knowledge of these variations provides a precautious approach by surgeons and other interventionists while working on this area.

Aberrant bifurcation of intercostobrachial nerve in the axilla: A case report.

Intercostobrachial nerve (ICBN) studies have been undertaken by many authors as it is a highly variable structure with numerous patterns reported worldwide. ICBN is a frequently damaged structure in Axillary Lymph Node Dissection (ALND) or mastectomy. Compression of this nerve, due to the enlargement of axillary lymph nodes from cancer breast may be presented as referred pain along the medial side of arm. Different patterns on the course and distribution of the ICBN have been described in literature. We encountered a lesser known variation of the ICBN where it pierced the second intercostal space as a single trunk and immediately divided into two branches. The putative clinical implications of this aberrant bifurcation are of value in significantly diminishing complications such as pain and sensory disturbances presenting after mastectomy and ALND. The findings of the presentation may be of use by surgeons and interventionists in approaching the area in a more precautious manner.