Hernia

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Hernia, the protrusion of an organ or part of an organ or other structure through the wall of the cavity that normally contains it. Hernias (incorrectly called ruptures) are qualified by the name of the part that protrudes or the area through which protrusion occurs. Thus, an inguinal hernia, perhaps the most common form, is one that passes through the abdominal wall in the groin area. A diaphragmatic or hiatus hernia is one in which part of the stomach or a loop of the intestine herniates upward through an opening in the diaphragm into the chest cavity. An umbilical hernia is one in which the bowel or the membranous apron overlying it, known as the omentum, protrudes through the abdominal wall under the skin at the navel.

Hernias often develop in an area of weakness following unusual stress or strain. An inguinal hernia, for example, may follow the abrupt lifting of a heavy object or a severe bout of coughing. Inguinal hernias are more likely to occur in men than in women because the spermatic cord passes through the abdominal wall in the inguinal region, leaving a site of natural weakness prone to hernia formation.

An inguinal hernia usually causes no distress, but hernias within the abdominal cavity can cause intense pain. Many hernias will slide back, or reduce, either spontaneously or when mild pressure is exerted on them. A reducible hernia is often held in place with an external support called a truss. Incarcerated (trapped) or strangulated hernias are often painful and must be treated with surgery because the blood supply to the organ trapped within the hernia can be interrupted, leading to gangrene within the hernial sac. Surgical repair involves reinforcing the site of the hernia with a sheet of synthetic mesh or with sutures.

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