Blood supply of the lower thoracic and lumbosacral regions. Postmortem aortography in 38 young adults.

Postmortem aortography was performed in 38 adults, aged 17 to 29 years, to elucidate the normal anatomy of the arteries supplying the lower thoracic and lumbosacral regions. The lowest 3 thoracic segmental arteries, examined in 32 cases, ran symmetrically in 27 cases. In 5 cases (16%) their course was asymmetric; on one side every segment was fed by an artery of its own, whereas on the other side a segmental artery fed 2 or more segments. The course, distribution and size of the 1st to 4th lumbar arteries were constant in every case except one, while the middle sacral artery and its branches, the 5th lumbar arteries, varied in size, being frequently compensated for, partly or wholly, by the iliolumbar arteries derived from the internal iliac arteries. In their course around the vertebral bodies, lumbar arteries frequently passed between and beneath fibrous attachments of the crura of the diaphragm and the psoas muscle.