Understanding an Incisional Hernia

What is an Incisional Hernia?

An incisional hernia is, quite simply, a hernia that occurs at the site of a previous surgical incision. Most often, these hernias occur within the front of the abdomen, at a site where a patient may have previously had surgery for abdominal surgical procedures such as an appendectomy, gallbladder removal, spleen removal, bowel resection, or really any other surgery on the abdomen where an incision is used to go through the abdominal layers and reach the internal organs.

Because all of the layers of the abdominal wall, including the muscle and fascia layers had to be breached, the site of the incision becomes a weak area. Even if the area is sewn together well at the end of the abdominal surgery, some of these incision sites will develop a hernia. These are some of the most frequent hernias we see in our practice.

What Are The Risk Factors For Incisional Hernias?

As we discussed above, just having the presence of an incision on your abdomen already carries significant risk of developing a hernia at that site. A large study revealed that a “laparotomy incision”, which is one of the most common types of incisions where a vertical incision down the mid portion of the abdomen is utilized to enter the peritoneal cavity, carries up to a 30% risk of developing a hernia at some point after the surgery.

Specific patient factors that increase the risk of developing an incisional hernia are infection of the surgery site, obesity, pregnancy after the original surgery, diabetes, radiation therapy or chemotherapy, and cigarette smoking.

As well, if multiple surgeries are performed through the same incision site, this increases the risk of developing a hernia at that site. Heavy lifting or straining of the abdominal muscles in the early postop period also increases risk of herniation. Most incisional hernias occur 3 to 6 months after surgery, but they can also occur many years after the original surgery.

How is an Incisional Hernia Diagnosed?

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If you notice a bulge at or very near a previous abdominal surgical scar, you may well have an incisional hernia. Most of these hernias are easy to diagnose during a physical exam by your healthcare provider or a surgeon specialist. Sometimes, if the hernia is small or it contains intra-abdominal fat which is “incarcerated” or “stuck” within the hole of the abdominal wall, it can be difficult to feel on exam.

When this is the case, imaging such as an ultrasound or a CT scan is the usual next step to determine the presence of the hernia. Imaging can also help determine the exact size of the hernia and evaluate for other hernias in the area which could have been missed on the exam. Therefore imaging can help plan the type of surgical approach to fix the hernia.

How is an Incisional Hernia Treated?

Unless a patient is unfit for surgery, most incisional hernias should be repaired when they are diagnosed. This is because these hernias increase in size over time and they are easier to repair with less chance of recurrence when they are small. An “open” approach where an incision is carried directly through the old scar to access and repair the hernia or a “laparoscopic” approach where small incisions are made away from the site of the original incision may be used for repair. Hernia mesh is usually required to repair these hernias in order to effect a low chance of recurrence since the patient has already failed one closure of the wound.

As the hernias grow in size over time, more surgery and advanced techniques are often required to repair them and they have a higher chance of recurring after that repair. If the hernia becomes too large, at some point these hernias may become such a high risk to the patient that repair is no longer possible. For patients that are too frail to have surgery, those patients that decline surgery, or who have gained too much weight to undergo successful repair, an abdominal binder may be used to help the symptoms related to the bulging hernia. The binder is usually made of an elastic material and it fits snugly around the abdomen to contain the area of bulge.

When is an Incisional Hernia Dangerous?

As with any other hernia, if an abdominal organ, such as the bowel, becomes trapped within the hernia and is “acutely incarcerated” or “strangulated” it can lead to rapid death of that organ or section of the organ. This may occur when the organ is pushed through the hole in the wall of the abdomen and the sides of the hole are so tight that it restricts blood flow. You can think of it as similar to putting a tight rubber band on your finger which would restrict the blood flow and cause swelling at the fingertip. Bowel can undergo “necrosis” or death of a certain segment stuck in the hernia within 6 hours of being trapped. Acute incarceration or strangulation in this case is usually associated with severe pain, firmness, and often redness or “erythema” at the site of the bulge. Seek immediate medical attention at the nearest emergency room if this occurs.