Rare high branching pattern from the first part of the right axillary artery.

A 77-year-old female cadaver was observed to have a rare branching pattern of the right axillary artery (AA). The first part of the AA typically gives off only a superior thoracic artery (STA) but was observed to give off three branches in the case: a lateral thoracic artery (LTA), a thoracoacromial trunk, and a large common trunk (CT). The LTA travelled to provide a variant STA to the 1st and 2nd intercostal spaces. The CT provided an accessory LTA and accessory thoracodorsal artery before bifurcating into a subscapular artery (SA) and posterior humeral circumflex artery. As expected, the SA further divided into the circumflex scapular artery and thoracodorsal artery. A pectoral artery and the anterior humeral circumflex artery originated directly from the second and third parts of the AA, respectively. Knowledge of AA branching variations is of great clinical significance to anatomists, radiologists, and surgeons due to the high rate of injury to this artery.