An unusual variation of the superficial ulnar artery.

Anomalous superficial ulnar arteries were found bilaterally during routine dissection of the upper limbs of a 60-year-old male cadaver. In the left arm, the superficial ulnar artery originated from the axillary artery. It crossed the median nerve anteriorly and ran anteromedial to this nerve and the brachial artery. The superficial ulnar artery was also rudimentary and gave rise to only a narrow muscular branch to the biceps brachii. In the hand, it anastomosed with the radial artery, completing the superficial palmar arch. The radial artery was larger than usual and the deep palmar arch was formed only by the radial artery. In the right arm, the superficial ulnar artery originated from the brachial artery at the level of the inter-epicondylar line. Additionally there were "inverse palmaris longus muscles" bilaterally. This was a rare case in which the superficially ulnar artery originated from a different source on each side accompanied by anomalies of the palmar arches on one side.