Illustration of a hiatus hernia with erosive, ulcerative esophagitis. A hiatus hernia occurs when the upper part of the stomach, which is joined to the esophagus, moves up into the chest through the hole (called a hiatus) in the diaphragm. It is common and occurs in about 10 per cent of people. Hiatus hernia can cause inflammation of the lower end of the esophagus. This is called reflux esophagitis, and it may result in the ulcerative condition seen here.