hiatal hernia, protrusion of a portion of the stomach upward through the diaphragm. The condition occurs in about 40% of the population, and most people display few, if any, symptoms. The major difficulty in symptomatic patients is gastroesophageal reflux, the backflow of the acid contents of the stomach into the esophagus. Diagnosis is made easily on x-ray films and may be an incidental finding of a chest radiogram. Surgical treatment is usually unnecessary, and efforts should be directed to alleviating the discomfort associated with reflux. See also diaphragmatic hernia, gastroesophageal reflux, heartburn.
