<P> The aortic hiatus is a hole in the diaphragm . It is the lowest and most posterior of the large apertures . </P> <P> It is located approximately at the level of the twelfth thoracic vertebra (T12). </P> <P> Strictly speaking, it is not an aperture in the diaphragm but an osseoaponeurotic opening between it and the vertebral column, and therefore behind the diaphragm (Meaning that diaphragmatic contractions do not directly influence the Aorta or aortic supply). </P> <P> Occasionally some tendinous fibers prolonged across the bodies of the vertebræ from the medial parts of the inferior ends of the crura pass posterior to the aorta, and thus convert the hiatus into a fibrous ring . </P>

Where does the aorta pass through the diaphragm