Variations of the A. axillaris and the crural arteries in the same human individual - multiple repetitions of the mammalian plesiomorphic constellation of the arteries

While dissecting the body of a 75-year-old female individual we observed “abnormal” patterns of the A. axillaris and the crural arteries which resembled the mammalian plesiomorphic constellation. In the right arm a large common trunk of the A. axillaris gave origin to the A. profunda brachii, the A. circumflexa humeri posterior, the A. circumflexa scapulae and the A. thoracodorsalis. In many other mammals including non-human primates, the Aa. circumflexae humeri and the A. circumflexa scapulae are connected via a third or fourth artery to a common trunk. Since the large common trunk mostly corresponded to the supply area of the A. axillaris, we consider it to be homologous to the distal part of the A. axillaris. In the left arm, except the A. circumflexa humeri posterior and the A. subscapularis which take off together, the other axillary branches showed the “normal” human pattern. In the right leg, the crural arteries exhibited the mammalian plesiomorphic constellation with an A. tibialis anterior ending in the crural extensor muscles, a rudimentary A. tibialis posterior, and a strongly developed A. peronea. In the left leg, the A. tibialis anterior supplied the Dorsum pedis and therefore represented the pattern normally seen in humans. However, in the left leg there also was a rudimentary A. tibialis posterior along with a prominent A. peronea.