What is a hernia?
A hernia is a weakness or hole in the stomach muscle wall through which stomach contents protrude causing a bulge. The protruding contents push out a pocket of the abdominal lining or peritoneum through the weakness forming the hernia.
Why do they occur?
There are areas of weakness in the muscle of the abdominal wall. The areas in which hernias most commonly develop are the umbilicus, the groin and where there has been an abdominal incision.
There is often an opening in the muscle layer at the umbilicus that may have been present since birth. It may enlarge due to anything that causes raised abdominal pressure, such as muscular strain or pregnancy, which may cause a hernia.
In male patients, blood vessels running through the groin muscles to the testicle create a weak area where an indirect inguinal hernia may develop. Strain or muscle deterioration can enlarge this weak spot and force abdominal contents through it resulting in the development of a hernia. Inguinal hernias may occur in women, although less commonly, and follow the round ligament of the uterus.
Other causes include incisions from old operations which may weaken the abdominal wall, if they do not heal properly after surgery or are weakened by infection. Muscle wall deterioration with age, inactivity or strain which may allow the muscle wall to tear or bulge, resulting in the development of various forms of hernias.
What types of hernia are there?
The most common type is inguinal or groin hernia. Herniae may also occur through the umbilicus (umbilical hernia), through old abdominal scars (incisional hernia), through the muscles in the upper abdomen (ventral hernia) or alongside blood vessels running into the thigh (femoral hernia). Laparoscopic repair is mainly used for inguinal or femoral hernia repairs, although increasingly ventral hernias are being repaired by laparoscopic techniques.