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.
Inguinal hernias appear in the crease of the groin or in the scrotum. They are more common among men. There are two types, direct and indirect, depending on exactly where the hernia occurs.
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).
A hernia may develop just below the crease of the groin in the middle of the thigh where the femoral artery and vein leave the abdomen to go into the leg. This type of hernia is more common among women.
Sometimes hernias form through a surgical incision in the abdominal wall. This type of hernia may develop many years after surgery.
Incarceration and Strangulation:
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.
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 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 blood supply of the testis develops varicose veins) or a spermatocele (a collection of sperm in a sac that develops next to the coiled tube where sperm are stored until they mature [epididymis]). Sometimes the doctor performs an ultrasound or a computed tomography (CT) scan to help make the diagnosis.
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.
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, repair is done at a time convenient for the person (elective surgery). Surgical repair aims to tighten 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 by tape, bandages, or 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 go away without treatment.
An inguinal hernia is a protrusion of a piece of intestine through an opening in the abdominal wall in the groin.
An inguinal hernia extends into the groin and can extend into the scrotum. Other types of hernias (such as umbilical hernias and femoral hernias) occur at other locations (see Gastrointestinal Emergencies: Abdominal Wall Hernias). With an inguinal hernia, the opening in the abdominal wall can be present from birth or develop later in life.
Inguinal hernias usually cause a painless bulge in the groin or scrotum. The bulge may enlarge when men stand and shrink when they lie down because the intestine slides back and forth with gravity. Sometimes a portion of the intestine is trapped in the scrotum (incarceration). If the intestine becomes trapped, the intestine's blood supply can be cut off (strangulation). Strangulated intestine may die (become gangrenous) within hours.
Inguinal hernias in women and those that cause symptoms in men should be surgically repaired. In men who have an inguinal hernia that does not cause any symptoms, surgery does not need to be done unless symptoms develop. Surgery can be done at a time convenient for the person. For strangulated and incarcerated hernias, emergency surgery is needed to pull the intestine out of the inguinal canal.
Last full review/revision October 2012 by Parswa Ansari, MD