A hernia occurs when an organ or fatty tissue squeezes through a weak spot in a surrounding muscle or connective tissue called fascia. The more common types of hernias are inguinal , incisional, ventral, femoral, umbilical (belly button), and hiatal. They do not get smaller with exercise or time. Even athletes and weight lifters with very strong muscles get hernias. They simply tend to get larger and more symptomatic as time passes so “watchful waiting” and the famous “don’t fix it till it bothers you” strategy does not offer any advantage unless the patient is too ill to get it fixed.
In an inguinal hernia, a layer of fat, the intestine or even the bladder protrudes through the abdominal wall or into the inguinal canal in the groin. Most groin hernias are inguinal, and most occur in men because of a natural weakness in this area.
In an incisional hernia, intra-abdominal fat and the intestines push through the abdominal wall at the site of previous abdominal surgery. This type is most common in elderly or overweight people after abdominal surgery. Multiple incisions through the same area or wound infections contribute to the appearance of this hernia. In general people who have abdominal surgery have about a 20% chance of developing this type of hernia.
Spontaneous hernia may develop in the abdominal wall for a variety of reasons. Repetitive heavy lifting, pregnancy and obesity with an accumulation of intradominal fat all increase the pressure in the abdomen That pressure can cause thinning of the abdominal wall and eventually tears or hernias develop. As time progresses these defects become large enough or painful enough that they must be fixed.
A femoral hernia occurs when intra-abdominal fat or the intestine enters the the tight, narrow canal that allows the femoral artery and vein to exit the pelvis and enter into the upper thigh. Femoral hernias are most common in women, especially those who are pregnant or obese. They can also appear in very thin patients. These hernias can be very painful and are often very difficult to feel on physical exam even in expert hands.
In an umbilical hernia, intra-abdominal fat or intestine passes through the abdominal wall near the navel. Common in newborns, it also commonly afflicts obese women or those who have had many children. It is a naturally occurring weak spot so it is not unusual to see it in men who engage in heavy lifting, coughing or other strains.
A hiatal hernia happens when the upper stomach squeezes through the hiatus which is a natural occurring gap in the diaphragm muscle through which the esophagus passes. This is NOT a abdominal wall problem although patients may express discomfort in the upper abdomen near the sternum.
Ultimately, all hernias are caused by a combination of pressure and an opening or weakness of muscle or fascia; the pressure pushes an organ or tissue through the opening or weak spot. Sometimes the muscle weakness is present at birth; more often, it occurs later in life. Issues that impede the healing of surgical incisions on the abdomen like diabetes, infection, coughing and straining before full healing has occurred will increase the rate of hernia formation. Some patients inherent a predisposition to poor wound healing with respect to collagen deposition by their body that creates increase rates of hernia formation even if all other issues are controlled.
Anything that causes an increase in pressure in the abdomen can cause a hernia, including:
In addition, obesity, poor nutrition, and smoking and pregnancy, can all weaken muscles and make hernias more likely.