The aortic hiatus is a hole in the
diaphragm. It is the lowest and most posterior of the large apertures.
It is located approximately at the level of the
twelfth thoracic vertebra
In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebrae and they are intermediate in size between the cervical ...
(T12).
Structure
Strictly speaking, it is not an aperture in the diaphragm but an