Hiatal Hernia Definition & Images

A Hiatal Hernia is an abnormality that involves the stomach, esophagus and the diaphragm.

A hernia is when a tissue, structure, or part of an organ extends beyond its boundary through muscle tissue or the area by which it is normally contained.

The diaphragm is a wall of muscle across the bottom of the rib cage. It separates the upper body cavity that contains the heart, lungs, etc. from the abdominal cavity that contains the stomach, intestines, etc. and it performs an important function in respiration (breathing).

Normally, the esophagus extends through the chest from the upper body cavity through a hole in the diaphragm into the abdominal cavity. That hole is called the esophageal hiatus. The esophageal hiatus joins the stomach just below the diaphragm.

When there is a hiatal hernia, the opening of the esophageal hiatus is larger than normal and a part of the stomach slips up, or passes (herniates), through the hiatus and into the upper cavity.