A hernia is an opening or weakness in the wall of a muscle, tissue or membrane that normally holds an organ in place. It is usually a sac formed by the lining of the abdominal cavity (peritoneum). The sac comes through a hole or weak area in the fascia, the strong layer of the abdominal wall that surrounds the muscle. Hernias happen more frequently in certain parts of the body, like the abdomen, groin, upper thigh and belly button area. They also can happen in any place where you may have had an incision from surgery. Hernias can cause pain and reduce general mobility. They never cure themselves, even though some can be cured (at least temporarily) by external manual manipulation. Depending on the nature of the protruding organ and the solidity of the structure through which it is protruding, a hernia may cause complications that are medically dangerous. One major danger of a hernia is that if bowel is contained within the protruding loop it may hinder or stop the flow through the intestine (occlusion). More serious still, if the loop itself becomes twisted outside its containing structure, or compressed at the point where it breaks through that structure (a strangulated hernia), the blood supply to the loop will also cease and the entire hernia will undergo tissue death (necrosis). This requires immediate emergency surgery.
There is no obvious cause of a hernia. Sometimes they occur with heavy lifting. They may be present at birth, but the bulging may not be noticeable until later in life. Further, some children may not have symptoms until they are adults. About 5 out of 100 children have inguinal hernias (more boys than girls). Hernias also tend to run in families, and can be caused by such things as coughing, straining during elimination, lifting heavy objects, accumulation of fluid in the abdominal cavity, pregnancy, chronic lung disease, cystic fibrosis, enlarged prostate or undescended testicles.
Hernias are normally classified by where they are found in the body. Although there are many types of hernias, the most common are:
Abdominal wall hernia: Also called an epigastric or ventral hernia; affects 1 person in 100 nationwide. Technically, this group also includes inguinal hernias and umbilical hernias. Indirect inguinal hernias affect only men. A loop of intestine passes down the canal from where a testis descends early in childhood into the scrotum. If neglected, this type of hernia tends to increase progressively in size (a “sliding hernia”) causing the scrotum to expand grossly. Direct inguinal hernias affect both sexes. The intestinal loop forms a swelling in the inner part of the fold of the groin.
Femoral hernia: This affects both sexes, although most often women. An intestinal loop passes down the canal containing the major blood vessels to and from the leg, between the abdomen and the thigh, causing a bulge in the groin and another at the top of the inner thigh.
Umbilical hernia: This affects both sexes. An intestinal loop protrudes through a weakness in the abdominal wall at the navel (but remains beneath the skin).
Hiatal hernia: This affects both sexes. A loop of the stomach when particularly full protrudes upward through the small opening in the diaphragm through which the esophagus passes, thus leaving the abdominal cavity and entering the chest.
Incisional hernia: This is a hernia that occurs at the site of a surgical incision. This is due to strain on the healing tissues due to excessive muscular effort, lifting, coughing or extreme pressure.
For small, non-strangulated and non-incarcerated hernias, various supports and trusses may offer temporary, symptomatic relief. However, the best treatment is herniorrhaphy (surgical closure or repair of the muscle wall through which the hernia protrudes). When the weakened area is very large, some strong synthetic material may be sewn over the defect to reinforce the weak area. Postoperative care involves protecting the patient from respiratory infections that might cause coughing or sneezing, which would strain the suture line. Recovery is usually quick and complete. As indicated above, emergency surgery is sometimes needed. The sac containing the intestine or other tissue may become stuck in the hole in the abdominal wall. If it cannot be pushed back through, this can lead to a strangulated loop of intestine. Left untreated, this portion of the intestine dies because it loses its blood supply.