What is a Hernia? Types of Hernias & Risk Factors
By William J. Symons, MD, FACS, Medical Director, Hernia Surgery
What is a hernia?
A hernia is a hole in the abdominal fascia, or the strong connective tissue upon which your muscles sit. While many types of hernias exist and everyone’s hernia is unique, there are common factors that put some people more at risk than others for developing hernias. It’s important to know that hernias can occur at any age, from birth to late adulthood. If you think you have a hernia, it’s important to seek medical attention as soon as possible.
What are some hernia risk factors?
- Anything that strains the abdominal wall can predispose a person to a hernia.
- Heavy lifting can increase intra-abdominal pressure and cause a hernia.
- Chronic coughing can lead to increased strain on the abdominal wall and hernia formation.
- Abdominal weight gain leads to stretching of the abdominal wall and the formation of hernias.
- During pregnancy, the body releases hormones to allow the abdominal wall to stretch. However, the hormones don’t completely counteract the strain on the abdominal wall and hernias can develop.
- Any surgical procedure on the abdominal wall weakens it and can lead to a possible hernia. The risk is greatly increased if a surgical site infection occurs as this inhibits normal healing of the fascia.
Some people are genetically more prone to hernia development. They have connective tissue/fascia that is inherently weaker than the general population.
What are the different types of hernias?
There are many different types of hernias. They come in all shapes and sizes, and are located in many diverse parts of the abdominal wall.
- Inguinal (Groin) Hernia: This is the most common type of hernia in both men and women. However, it is about ten times more likely to occur in men. In males, it happens when an opening in the abdominal wall from the passage of the testicle into the scrotum does not close normally before birth, or reopens later in life. In women, this canal contains the round ligament (the area that surrounds and supports the uterus) and is much smaller but still exists and can reopen later in life.
- Femoral Hernia: Appears as a bulge near the groin or thigh. This type of hernia is not common and usually occurs in elderly, thin females. It is due to an enlargement of the small hole in the abdominal fascia needed for the major blood vessels of your leg. Less than 5% of all hernias are femoral hernias.
- Umbilical Hernia: As an unborn baby develops during pregnancy, there is a small opening in the abdominal wall, where the umbilical cord passes from the unborn baby to the mother and provides all of the nutrients for life. After birth, this opening closes but is an area of weakness in the abdominal wall. Over time, and with strain, this area of weakness can reopen. A loop of intestine can then move into the opening, causing an umbilical hernia.
- Incisional Hernia: Usually occurs months, or years, after surgery in the area overlying the scar. The size of this type of hernia depends on the initial surgery.
- Epigastric Hernia: Normally present in the middle of the belly between the breastbone and the belly button. In the mid-line, the fascia is not covered with muscle and is a natural area of weakness. Fat or intestine can push through a weak spot in the abdominal wall.
- Hiatal Hernia: Is the most common form of a diaphragm hernia. The diaphragm is a large, flat muscle that separates the chest from the abdomen. Normally, the chest and abdomen communicate to allow the esophagus to enter into the abdomen and connect to the stomach. Over time, this area can stretch and part of the stomach can bulge up through the diaphragm and into the chest. Many people don’t feel symptoms; however, heartburn can be a common sign.
- Spigelian Hernia: A hernia located on the side of the rectus muscle, or 6-pack. This is an area of weakness as it is a location where fascia meet and is not covered by muscle. Spigelian hernias are rare hernias that are sometimes harder to diagnose with a physical exam alone as they don’t always display the typical "hernia bulge."
- Lumbar Hernias: Hernias that reside further back in the abdominal wall that often have a visible bulge toward the side. These hernias are the result of trauma, prior surgery or sometimes congenital (at birth).
- Obturator Hernia: A rare hernia of the pelvic floor. These types of hernias can be difficult to diagnose on physical exam and require a high degree of suspicion on the part of the clinician. They often require a CT scan of the pelvis to correctly diagnose.