Hernias are most common in the abdomen, but they can also appear in the upper thigh, belly button, and groin areas. Most hernias are not immediately life threatening, but they don’t go away on their own and can require surgery to prevent potentially dangerous complications.
Types of Hernia
Inguinal hernias are the most common type of a hernia. They represent approximately two-thirds of adult hernias and are much more common in men than in women. They occur in a part of the abdominal wall known as the inguinal canal, where a man’s testicles must descend before birth. It leaves a natural defect called the internal inguinal ring that can develop into a hernia if it doesn’t seal properly. As a result, the contents of the abdomen, such as intestine, may protrude through the opening, creating pain and a bulge.
Inguinal hernias are located in the lower abdomen just above the leg crease, near or adjacent to the pubic area. They can sometimes occur on both sides of the pubic area, and if they do, they are called bilateral inguinal hernias. Inguinal hernias, along with femoral hernias make up the two types of groin hernias and can produce pain that extends into the upper thigh or scrotum.
Inguinal hernias can be classified as “direct” or “indirect.”
An indirect inguinal hernia occurs through the natural weakness in the internal inguinal ring.
A direct inguinal hernia is a result of weakness in the floor of the inguinal canal and is more likely to develop in older men over the age of 40. The floor of the inguinal canal is located just below the internal inguinal ring.
When inguinal hernias are repaired with a technique called tension repair, recurrence rates may be higher than 15%, which means that a hernia may reappear in time.1 Other hernia repair techniques, such as tension-free and laparoscopic tension-free, have much lower recurrence rates. See Methods of Repair for more information.
A hernia that appears in the abdomen at the site of a previous surgery is known as a ventral or an incisional hernia. These hernias can appear weeks, months, or even years after surgery and can vary in size from small to very large and complex. If you think you have a ventral hernia, it’s important to see your doctor because it may widen and become tough to repair. When repaired with a technique called tension repair, ventral hernias have a 50% recurrence rate.2 Other hernia repair techniques, such as tension-free and laparoscopic tension-free, have much lower recurrence rates. See Methods of Repair for more information.
Femoral hernias, along with inguinal hernias are groin hernias. They are much more common in women but can occur in men. These hernias appear just below the groin crease and are usually the result of pregnancy and childbirth. A weakness in the lower groin allows an intestinal sac to drop into the femoral canal, a space near the femoral vein that carries blood from the leg. These hernias are more prone than inguinal hernias to develop incarceration or strangulation as an early complication. Therefore, once these hernias are diagnosed, early repair is very strongly advised before such complications occur.
Umbilical hernias occur near the bellybutton or navel, which has a natural weakness from the blood vessels of the umbilical cord. These hernias may occur in infants at or just after birth and may resolve by three or four years of age. However, the area of weakness can persist throughout life and can occur in men, women, and children at any time. In adults, umbilical hernias will not resolve and may progressively worsen over time. Abdominal pressure sometimes causes them due to being overweight, excessive coughing, or pregnancy. When repaired with a technique called tension repair, umbilical hernias have an 11% recurrence rate.3 Other hernia repair techniques, such as tension-free and laparoscopic tension-free, have much lower recurrence rates.
Epigastric hernias are more common in men than in women. They occur due to weakness, gap, or opening in the muscles or tendons of the upper abdominal wall, on a line between the breast bone and the navel or umbilicus.
Hiatal hernias are slightly different from other types of hernias because they are a weakness or opening in the diaphragm, which is the muscle that separates the chest cavity from the abdominal cavity. These hernias cause reflux of acid from the stomach into the esophagus, which can lead to heartburn, pain, and erosion of the esophagus. Surgery to repair this type of a hernia is usually more complicated and may require a longer hospital stay.
Acquired vs. Congenital Hernias
Hernias can also be classified by when they occur. A person may be born with a hernia, or a hernia may be acquired from daily activity.
- Acquired hernias are caused by the wear and tear of living, such as childbirth, weight gain, and other muscle strain.
- Congenital hernias are present from birth and happen at points of weakness in the abdominal wall. Children’s hernias are almost always congenital.
Reducible vs. Nonreducible Hernias
A hernia with a bulge can be classified based on whether or not the bulge can be flattened.
- A reducible hernia is a hernia with a bulge that flattens out when you lie down or push against it gently. This type of hernia is not an immediate danger to a person’s health, although it may be painful and worsen over time if left untreated.
- A nonreducible hernia occurs when the loop of the intestine becomes trapped, and a person loses the ability to make the bulge flatten out. Nonreducible hernias are often very painful and require prompt medical attention.
Potentially Life-Threatening Hernias
Hernias can also be classified based on their status and severity. An incarcerated hernia or obstructed hernia is one in which the tissues have become trapped. It is also called a nonreducible hernia and is very serious because it may lead to the intestine or tissue strangulation. A strangulated hernia happens when part of your intestine or other tissue becomes tightly trapped, and the blood supply is cut off. Strangulated hernias can result in gangrene. This condition is considered a medical emergency and requires immediate surgery to undo the blockage and repair a hernia.