A hiatal hernia is a condition in which a weakened diaphragm with a structural defect allows the stomach to pass into the chest through the esophageal diaphragmatic opening (hiatus). Three types of the condition include:

• Sliding hiatal hernia - both the stomach and the gastroesophageal junction slide into the chest and are above the diaphragmatic opening.

• Paraesophageal hiatal hernia - the greater curvature of the stomach rolls through the diaphragmatic defect.

• Mixed - a combination of sliding and paraesophageal.

The sliding type is most common.

The cause is not always known. However, a muscle weakening may be related to the following circumstances: congenital abnormality; aging; kyphoscoliosis; trauma; a surgical procedure or esophageal cancer.

The following complaints occur in the sliding type: heartburn due to gastric reflux, or vomiting 1 to 4 hours after eating or both; and substernal chest pain occurring mostly after meals and at night when in recumbent position. Those with a paraesophageal hernia have few, if any, symptoms, but may experience sensations of fullness in the chest or pain like that of angina pectoris. The paraesophageal hernia may possibly incarcerate or strangulate. Large hernias (a greater portion of the stomach is above the diaphragm) can cause bleeding and anemia.

Diagnostic measures include: chest x-ray; barium study; endoscopy; esophageal motility studies; measurements of pH; and an acid perfusion test.

Surgery is required for a paraesophageal hernia. If medical treatment with antacids, histamine blockers, and cholinergic agents do not control symptoms in sliding hernias, then surgical treatment will be used.

A postoperative recovery will usually require 6 to 8 weeks, and patients are advised to refrain from activities that increase intra-abdominal pressure. Meals should be small, frequent and bland. Medically treated patients are advised to lose weight, eat small, frequent meals that are not spicy, and to avoid coffee, alcohol and smoking. The head of the bed should be elevated 6 inches, and coughing and straining should be avoided.

• Gastroesophageal reflux disease (GERD) is a common diagnostic term used for symptomatic hiatal hernia. This disorder does not share pathology with (i.e., is not necessarily related clinically to) peptic ulcer disease, which can (and often does) co-exist with GERD. If the two conditions happen to co-exist, service connection of one would be determined independently of the other.

• Ratings under diagnostic codes 7301 to 7329, inclusive, 7331, 7342, and 7345 to 7348 inclusive will not be combined with each other. A single evaluation will be assigned under the diagnostic code which reflects the predominant disability picture, with elevation to the next higher evaluation where the severity of the overall disability warrants such elevation. [38 CR 4.114]

• For purposes of evaluating conditions in 38 CFR 4.114, the term “substantial weight loss” means a loss of greater than 20 percent of the individual's baseline weight, sustained for three months or longer; and the term “minor weight loss” means a weight loss of 10 to 20 percent of the individual's baseline weight, sustained for three months or longer. The term “inability to gain weight” means that there has been substantial weight loss with inability to regain it despite appropriate therapy. “Baseline weight” means the average weight for the two-year-period preceding onset of the disease. [38 CFR 4.112]

• There are diseases of the digestive system, particularly within the abdomen, which, while differing in the site of pathology, produce a common disability picture characterized in the main by varying degrees of abdominal distress or pain, anemia and disturbances in nutrition. Consequently, certain coexisting diseases in this area, as indicated in the instruction under the title “Diseases of the Digestive System,” do not lend themselves to distinct and separate disability evaluations without violating the fundamental principle relating to pyramiding as outlined in 38 CFR 4.14.  [38 CFR 4.113]