Hiatal hernia occurs when the upper part of the stomach bulges through the diaphragm, the large muscle that separates the abdomen and chest.
The diaphragm has a small opening (hiatus) through which the esophagus passes: in a hiatal hernia, the stomach pushes through the diaphragm from its normal location, the abdomen, to the chest.
A small hiatal hernia usually causes no problems and goes unnoticed unless the doctor discovers it when another condition occurs.
But alarge hiatal hernia is symptomatic and is prone to complications, for example, it can compress an adjacent part of the chest, and there can also be insufficiency phenomena.
