Morphology of the terminal aorta

We evaluated the termination of the abdominal aorta in relation with the vertebral column in 142 cases, finding it between middle 1/3 of the L3 vertebra and L5-S1 intervertebral disc. At the level of the L4 vertebra the abdominal aorta ends in 71 of the cases, following, in the order of the frequency, the L4-L5 intervertebral disk with 40 cases, the L5 vertebra with 14 cases, the L3-L4 intervertebral disc with 10 cases, the L3 vertebra with 6 cases and only in one case at the L5-S1 intervertebral disc. The aortic termination above the L4 vertebra was considered a high termination, 11.27% of cases, and the origin below the L4-L5 intervertebral disc was considered a low termination, 10.56% of cases. The bifurcation of the aorta in relation to mid-vertebral line was assessed on 138 cases, with 79 cases on the left, 38 on the midline and in 21 cases the aortic bifurcation was right to the midline. The distance between the aortic bifurcation and the sacro-vertebral joint (promontory) was between 40 - 82 mm. The aortic bifurcation related to the origin of the inferior vena cava was assessed on 38 cases, finding that most frequently, in 27 cases, the bifurcation was above the level of origin of the inferior vena cava, with a distance of between 2 - 3 mm and up to 45 mm. In 7 cases it was located below the origin of the inferior vena cava and in 4 cases the aortic bifurcation was located at the same level with the origin of the inferior vena cava.