RESUMEN
The presence of an upper subscapular nerve branching from the posterior division of the superior trunk, and it being accompanied by an accessory subscapular artery, is of both clinical and surgical significance. During routine dissection of the root of the neck in a 75-year-old male cadaver, an unusual branch from the third part of the right subclavian artery was observed lateral to the dorsal scapular artery. Continued dissection revealed that this artery traveled between the anterior divisions of the superior and middle trunks of the brachial plexus before traveling alongside a nerve from the posterior division of the superior trunk of the brachial plexus. This artery and nerve descended on the anterior aspect of the subscapularis muscle before piercing into its muscle belly. We believe this to be a previously unreported unique variation of the upper subscapular nerve that is accompanied by an accessory subscapular artery on its course to the subscapularis muscle. Knowledge of anatomical variations like this may lead to decreased complications in nerve blocks and surgical procedures related to the shoulder.
RESUMEN
The presence of both a superficial ulnar artery (SUA) and persistent median artery (PMA) of antebrachial type is of both clinical and surgical significance. In an 84-year-old female cadaver received through the Gift Body Program at Saint Louis University School of Medicine, the right brachial artery was seen divided into an SUA and radial artery (RA) slightly below the interepicondylar line of the humerus. At the level of the radial neck, the RA sent out the common interosseous artery that then gave off the radial recurrent artery before bifurcating into anterior interosseous artery (AIA) and posterior interosseous artery. The AIA continued to appear to branch into the anterior ulnar recurrent artery and posterior ulnar recurrent artery, as well as a PMA of the antebrachial type. In the hand, the SUA and RA contributed to the complete superficial palmar arch seemingly equally, and the RA was the dominant contribution to the deep palmar arch. Ninety-one other arms were assessed for this variation, and none were observed. Knowledge of an anatomical variation such as this may lead to decreased complications in the planning of surgical bypass grafting.