Hiatushernia

A hiatal hernia is an abnormal protrusion of the stomach or other abdominal structures through the esophageal hiatus into the thoracic cavity.

Under normal physiological conditions, the gastroesophageal junction or GEJ is securely positioned below the diaphragm, anchored by the phrenoesophageal membrane, diaphragmatic crura, and surrounding connective tissues.

These structures can weaken with age or with sustained increases in intra-abdominal pressure, as seen during pregnancy or with activities like heavy lifting.

This weakening may enlarge the esophageal hiatus, allowing the GEJ and parts of the stomach to herniate upward into the thoracic cavity.

Hiatal hernias are classified into four types. Type I, or sliding hernia, involves the upward movement of the GEJ into the thoracic cavity.

Type II, or paraesophageal hernia, occurs when the gastric fundus herniates beside the esophagus.

Type III combines both, with displacement of the GEJ and the fundus.

Type IV involves herniation of the stomach along with other abdominal organs, such as the small intestine.