The anatomy of the fourth and fifth lumbar arteries in humans: an arteriographic study in one hundred live subjects.

The anatomy of the arteries on the anterolateral surfaces of the lower two lumbar vertebral bodies has been described in 100 living subjects, using radiographs obtained at aortography. The classic description of this anatomy is commonly correct in the young subject. In addition, a precostal anastomosis was seen in 5 out of 7 subjects aged 10 years or younger. Distortion of this pattern was seen in older subjects; most of this distortion was due to degenerative disease. The average number of observed arteries around the fifth lumbar vertebral body declined steadily in decennial age groups over 30 years, but a statistically significant difference could not be found between the categories of indications for aortography, nor between those judged grossly atherosclerotic and those not so judged as a result of aortography. The precostal anastomosis is an important collateral supply in some older subjects with arterial disease. In addition, a common artery of origin for the fourth lumbar arteries was observed in 15 subjects, and an origin from the median sacral artery for the fourth lumbar arteries was observed in two subjects. These features have not previously been described in healthy subjects.