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 during respiration do not directly affect aortic blood flow[3]).[citation needed]
The hiatus is situated slightly to the left of the midline, and is bound anteriorly by the crura, and posteriorly by the body of the first lumbar vertebra.[citation needed]
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.[citation needed]
Contents
The aorta is situated on the left, the thoracic duct in the middle, and the azygos vein on the right.[1]: 185 The hemiazygos vein may pass through the aortic hiatus[2] or may pass through the diaphragm independently through its own foramen in the left crus.[1]: 186
^ abcdeMoore, Keith L.; Dalley, Arthur F.; Agur, Anne M. R. (2017). Essential Clinical Anatomy. Lippincott Williams & Wilkins. p. 536. ISBN978-1496347213.
^Moore, Keith L.; Dalley, Arthur F.; Agur, Anne M. R. (2017). Essential Clinical Anatomy. Lippincott Williams & Wilkins. p. 536. ISBN978-1496347213.
External links
Anatomy photo:40:08-0103 at the SUNY Downstate Medical Center - "Major Openings in the Diaphragm"