Abnormal Passage of Oesophagus through the Diaphragm – A Case Report

Diaphragm is a musculo-aponeurotic sheet separating thoracic and abdominal cavities. It has few apertures in it providing passage for structures traversing between both the cavities. Out of those, oesophageal hiatus (OH) has got more surgical importance as it goes through muscular portion of diaphragm and is prone to changes in hiatal diameter due to excursions of diaphragm. This should lead to stomach herniation into thoracic cavity and acid reflux with inspiration but it is prevented by the arrangement of crural diaphragm around the OH and angle at the entry of oesophagus into stomach as studied by Collis et al. However, due to age or congenital defects, above mentioned pathologies do occur. This has led to pronounced research into normal anatomy of OH and most of the studies have found that right crus provides significant contribution to OH margins. During cadaveric dissection at our college in the department of Anatomy, we have a found OH, in a cadaver, bounded by the crura on both sides and median arcuate ligament anteriorly. Aorta and other routinely found structures are seen passing through the same hiatus posterior to the oesophagus. Precise knowledge about oesophageal hiatus is essential for better understanding of physiological and clinical phenomena