Absence of the brachial artery: Report of a rare human variation and review of upper extremity arterial anomalies

Variations in the arterial anatomy of the upper extremities, although uncom mon, occur in up to one in five patients. Most of these variants occur in e ither the radial or ulnar artery; brachial artery variations are less commo n. The case we report is a rare anomaly consisting of brachial artery agene sis or regression. The brachial artery was absent from its origin but recon stituted as a normal-appearing vessel 3 cm above the antecubital fossa, The profunda brachii artery and the superior and inferior ulnar collateral art eries were also absent in this patient. The axillary artery served as the m ain collateral to the forearm. This constellation of anomalies has not been previously described or explained by developmental models in humans and ot her primates. We speculate that failure of development or arrest of specifi c vascular anlage in the upper extremity occurs at particular embryological stages because of unknown factors.