Common trunk of the posterior intercostal arteries from the thoracic aorta: anatomical variation, frequency, and importance in individuals.

It is important to recognize this anatomical variation when the number of origins of the posterior intercostal arteries from the thoracic aorta due to the multiple common trunk present can be reduced, as their origins and vascular territories are involved in primary diseases of the thoracic aorta, like atherosclerosis, aneurysm, or dissection that lead to serious complications. For example, in thoracoabdominal aneurysm repair, reimplantation of the posterior intercostal arteries is recommended to avoid potential ischemic injury to the supplying areas, especially to the spinal cord.