Abdominal Wall Hernias
An abdominal wall hernia is a protrusion of the intestine through an opening or area of weakness in the abdominal wall.
Abdominal hernias are very common, particularly among men. There are about 700,000 hernia operations each year in the United States. Hernias are usually named for the area in which they occur.
The abdominal wall is thick and tough in most places, so hernias usually occur in an area of weakness where a previous opening has closed. Heavy lifting or straining may make a hernia more obvious but does not cause a hernia to form.
Umbilical hernias occur around the navel (umbilicus). Many babies have a small umbilical hernia because the opening for the umbilical cord blood vessels did not close completely. In younger children, doctors sometimes monitor umbilical hernias to see whether they close on their own.
Some adults have an umbilical hernia because of obesity, pregnancy, or excess fluid in the abdomen (ascites).
Sometimes, a loop of intestine becomes stuck in the hernia, a condition called incarceration. An incarcerated hernia can block (obstruct) the intestine. Rarely, the hernia traps the intestine so tightly that it cuts off the blood supply, a condition called strangulation. With strangulation, the trapped piece of intestine can develop gangrene in as few as 6 hours. With gangrene, the intestinal wall dies, usually causing rupture, which leads to peritonitis (inflammation and usually infection of the abdominal cavity), shock, and, if untreated, death. (See figure: What Causes Intestinal Strangulation?.)
A sports hernia is not a true hernia because there is no opening or weakness in the abdominal wall. There is also no protrusion of abdominal contents. Instead, the disorder involves a tear of one or more muscles, tendons, or ligaments in the lower abdomen or groin, particularly where they attach to the pubic bone. The term sports hernia may have come about because the pain occurs in the same area as an inguinal hernia.
Most people usually notice only a bulge at the site of the hernia. Sometimes the hernia appears only with lifting, coughing, or straining. There is usually little or no discomfort, and the bulge can be pushed back in (reduced) by the person or a doctor.
An incarcerated hernia has no additional symptoms, but the bulge cannot be reduced.
A strangulated hernia causes steady, gradually increasing pain, typically with nausea and vomiting, cannot be reduced, and is tender when touched.
Doctors base the diagnosis of hernias mainly on an examination. Lumps in the groin that resemble hernias may be swollen lymph nodes or undescended testes. A swelling in the scrotum may be a varicocele (a condition in which the veins that carry blood from a testis widen) or a spermatocele (a cyst in a sac that develops next to the coiled tube where sperm are stored until they mature [epididymis]).
Umbilical hernias in infants rarely strangulate and are not treated. Most go away without treatment within several years. Very large umbilical hernias may be repaired after the infant is 2 years old.
Umbilical hernias in adults cause cosmetic concerns and can be repaired at a time that is convenient for the person (called elective surgery). Although umbilical hernias in adults do not usually strangulate and incarcerate, these complications can occur.
Because other types of hernias are more likely to strangulate, doctors usually repair them surgically when they are diagnosed. If the hernia is incarcerated or strangulated, surgery is done immediately. Otherwise, elective surgery is done. Surgical repair aims to tighten or cover the opening so the abdominal contents cannot slide back out. Surgery usually relieves the symptoms of a hernia, depending on its size and the amount of discomfort it caused.
Holding the hernia in with tape or bandages or by other means sometimes makes the person more comfortable but does not lower the risk of strangulation or allow the opening to close. Therefore, these are not recommended treatments. Only umbilical hernias in infants go away without treatment.