A spigelian hernia is a hernia through the spigelian fascia or layer of tissue that separates two groups of abdominal muscles. The muscles are called the rectus muscles and the lateral obliques.
This type of hernia is also sometimes called a lateral ventral hernia. Unlike most hernias, spigelian hernias do not typically develop below layers of fat but rather between muscles and the fascia — tissue that connects them.
If left untreated, a spigelian hernia can block a portion of the bowel or cut off the blood supply to other organs and tissue. This condition can be life-threatening.
The symptoms of a spigelian hernia can be similar to other hernias in the abdomen. This means that it is impossible to diagnose a spigelian hernia based on symptoms alone.
Because of their location between muscle layers, spigelian hernias tend not to cause noticeable swelling. Very thin people with visible abdominal muscles may notice some swelling, however.
Most people with a spigelian hernia experience abdominal pain or vague discomfort, especially when straining the abdominal muscles, such as when lifting or straining to have a bowel movement.
Some symptoms to watch for include:
- pain in the abdomen that seems unrelated to food, illness, or other common sources
- sudden changes in bowel function, such as constipation or a change in stool or bleeding
- abdominal pain when lifting, coughing, or having a bowel movement
- a soft, unexplained swelling in the abdomen
Most people do not feel a swelling, and there does not need to be a noticeable swelling for there to be a spigelian hernia.
A spigelian hernia can occur on either side of the abdomen, but most people feel pain in the lower abdomen.
A spigelian hernia can block the bowel or other vital organs. When this occurs, it is a life-threatening complication that requires immediate medical attention.
Symptoms of a blockage include:
- intense, unbearable abdominal pain that may come on suddenly or appear after a long period of less severe pain
- nausea and vomiting accompanied by severe pain, particularly when seemingly unrelated to food or a virus
- not having a bowel movement for several days, especially if this is accompanied by intense stomach pain
- the appearance of blood in the stool
Spigelian hernias develop within a weakened area in the abdominal wall muscles.
The weakened area can be something a person is born with, or it can develop over time. If it develops over time, it can be because of an injury or increased pressure within the abdominal cavity. This weakened area allows tissue and organs to poke through the spigelian fascia.
Risk factors for a spigelian hernia include:
- a chronic cough, such as with the lung condition COPD
- frequently straining to have a bowel movement
- trauma to the abdomen, such as during surgery or due to a major injury
- frequently straining to lift heavy objects
- fluid in the abdomen due to conditions such as liver problems
- being overweight
- being pregnant
It may also be useful to consult a general surgeon, as these specialists have extensive knowledge of hernias, including spigelian hernias.
A spigelian hernia may also be discovered during surgery or procedures performed for other reasons, including:
- a bowel obstruction or blockage
- exploratory surgery
- surgery for another type of hernia
- gynecological surgery
- colonoscopy for colon cancer screening
To diagnose a spigelian hernia, a doctor will take a complete medical history and will perform an exam to rule out other medical issues.
An ultrasound can detect most cases. Doctors also sometimes use computed tomography or CT scans. Both are safe and non-invasive diagnostic tests that allow a doctor to visualize the muscles, intestines, and abdominal wall.
However, if the diagnosis is not clear, a doctor may suspect that a hernia is present without knowing which type. They may decide to carry out exploratory surgery to locate and repair the hernia.
A spigelian hernia requires surgery for it to be repaired.
A minimally invasive surgery called laparoscopic hernia repair uses a small incision to guide a tube and a camera into the abdomen. With the assistance of the camera, doctors locate the hernia then use a mesh patch or stitches to repair the weakened abdominal wall.
A more invasive alternative involves a larger incision into the stomach. This surgery allows a doctor to directly view the hernia then make repairs to the damaged tissue.
A 2002 study compared laparoscopic and more conventional invasive surgery to repair spigelian hernias in two groups of 11 people. Laparoscopic surgery produced fewer complications. This suggests that it may be a preferred option for most people without complex hernias.
When a spigelian hernia traps a portion of the bowel, surgery may need to be performed immediately. Surgery may also take longer and be more complex, depending on how extensive the involvement is of the bowel and other tissues and organs.
The recovery period for laparoscopic spigelian hernia surgery tends to be relatively short, lasting just 1 to 2 weeks. People who have more extensive surgery often have a longer recovery period.
People who experience complications, such as a bowel obstruction or an infection, may also require longer recovery times.
A person should report any new symptoms to a doctor. Fever, intense pain, or unexplained bleeding may mean that there are complications with recovery.
Most people can resume normal activities within 4 to 6 weeks and can begin light activities, such as walking and driving, 1 to 2 weeks following surgery. A person should strictly follow their surgeon’s recommendations and advice for the best possible outcomes during recovery.
People who have previously had a hernia are more likely to experience another hernia. However, a 2002 study followed up with 76 people who had undergone spigelian hernia surgery an average of 8 years later. It found just three had experienced another hernia.
The results suggest that most people who receive surgery for a spigelian hernia are unlikely to have another hernia in the following years. Their risk, however, remains higher than that of people with no history of hernias.
It can feel tempting to delay seeking treatment for sudden abdominal pain. This reaction may be especially true if the pain goes away for a while. However, spigelian hernias present serious medical risks.
They are relatively easy to treat, and most people will not need surgery again. So, when signs of a spigelian hernia appear, people should see a doctor.