Rectus Sheath Hematoma

What is the rectus sheath?

Your rectus sheath is a fibrous connective tissue (aponeurosis) that contains two of your abdominal muscles: your rectus abdominis and pyramidalis. Your rectus sheath has a front (anterior) wall and a back (posterior) wall. These walls are an extension of the fascia that surround other muscles in your abdomen:

• Your external abdominal obliques.
• Your internal abdominal obliques.
• Your transversus abdominis.

Your rectus sheath also contains your upper (superior) and lower (inferior) epigastric arteries. These are the main arteries that supply blood to your abdominal muscles. Your rectus sheath protects the organs, muscles and blood vessels within your abdominal walls.

But your rectus sheath doesn’t completely enclose its contents. Both the anterior and posterior rectus sheath wrap around the upper part of your rectus abdominis. The line between the upper and lower parts of your rectus abdominis is called the arcuate line. This line runs one-third of the way between your belly button (navel) and the joint that connects your right and left pelvic bones (pubic symphysis).

Below the arcuate line, your anterior rectus sheath covers the lower part of your rectus abdominis. But the posterior rectus sheath is missing (absent), so there’s nothing to protect the lower part of the back of your rectus abdominis.

What is a rectus sheath hematoma?

A hematoma is a collection of blood within your tissues. Any bleeding from the epigastric arteries contained within the rectus sheath can spread into and build up in your abdomen. This condition is more significant when it involves the inferior epigastric artery. This is because there isn’t tissue to stop blood from spreading below the posterior part of the arcuate line.

Who do rectus sheath hematomas affect?

Rectus sheath hematomas affect people assigned female at birth more often than people assigned male at birth. They’re most common in people over the age of 60.

How common are hematomas of the rectus sheath?

Rectus sheath hematomas are rare. They’re responsible for only 1% to 2% of all causes of abdominal pain.

What are the symptoms of a rectus sheath hematoma?

The most common symptom of a rectus sheath hematoma is abdominal pain. The pain may come on suddenly and feel sharp, severe and persistent. It may also worsen when you move or flex your abdominal muscles. You may also be able to feel a mass in your abdomen. Other symptoms may include:

• Nausea and vomiting.
• Fever.
• Bruising.
• Anemia.
• Fast heart rate (tachycardia).
• Low blood pressure (hypotension).

What causes a hematoma of the rectus sheath?

Rectus sheath hematomas result from bleeding into your rectus sheath. It most commonly occurs due to abdominal wall trauma.

Rectus sheath hematomas can occur when you injure an epigastric artery, its branches within your rectus abdominis or the muscle itself. The blood supply to your abdominal muscles comes from your superior and inferior epigastric arteries. Rectus sheath hematomas are more serious when they involve the inferior epigastric artery. This is because it doesn’t have the protection of your posterior rectus sheath until it reaches the arcuate line.

When you endure direct trauma or excessive force to your abdominal wall, an epigastric artery can rupture, causing a hematoma.

What are the risk factors for developing a rectus sheath hematoma?

The biggest risk factor for developing a rectus sheath hematoma is the use of blood thinners (anticoagulants). Almost 70% of people who develop a rectus sheath hematoma are on some form of anticoagulation.

Another risk factor appears to be chronic kidney disease. Almost 60% of people who developed a rectus sheath hematoma had stage III or higher kidney disease.

Other risk factors may include:

• Recent abdominal surgery.
• Steroid or immunosuppressant therapy.
• Forceful coughing.
• Antiplatelet therapy.
• Pregnancy.
• Chronic medical conditions, such as hypertension and atherosclerosis.

How is a rectus sheath hematoma diagnosed?

A rectus sheath hematoma can be difficult to diagnose because its symptoms are similar to other medical conditions.

Your healthcare provider will request tests to measure your hemoglobin and hematocrit levels. More than half of people with a rectus sheath hematoma had significantly low levels of hemoglobin.

Your provider will usually request an ultrasound of your abdominal wall as an initial imaging test. The ultrasound can show fluid collection within your abdominal wall and possibly show the size of your hematoma.

They may also request a CT scan, which can be even more sensitive and specific. A CT scan with contrast (dye) is preferred, because it can show where the dye has escaped from an injured artery. This can tell your provider where the rupture occurred.

How is a hematoma of the rectus sheath treated?

Most rectus sheath hematomas clear up on their own and don’t require medical treatment. You can typically treat a hematoma with ice or cold compresses, rest and over-the-counter pain killers (analgesics). About 80% of rectus sheath hematomas go away with these types of conservative treatment.

If these methods fail or you have an advanced case, your healthcare provider may perform an angioembolization. This noninvasive procedure combines angiography (imaging of your blood vessels) and embolization (closing off your blood vessels) to see and block off the bleeding artery.

If angioembolization doesn’t work, your provider may perform surgery. During surgery, they’ll remove the hematoma and close off the bleeding artery.

Your healthcare provider will continue to watch your condition with blood tests and ultrasounds. This can detect early signs of bleeding again as well as infections.

What can I expect if I have a rectus sheath hematoma?

Most rectus sheath hematomas disappear on their own within two to three months. Many people with the condition recover well and have no further complications.

However, in some cases — especially in people who take blood thinners — the condition can be fatal. Most recent data suggests less than 2% of cases of rectus sheath hematoma cause death. Like many conditions, early diagnosis and treatment improve your chances of survival. See your healthcare provider if you have any symptoms of a rectus sheath hematoma.

A note from Cleveland Clinic

Your rectus sheath protects the organs, muscles and arteries within your abdominal walls. When you endure trauma to your abdominal wall, you can rupture an epigastric artery, which can cause a rectus sheath hematoma. Most rectus sheath hematomas don’t require medical treatment. You can typically ice it, rest and take over-the-counter pain relievers. However, some cases are more serious. If you have severe abdominal pain, see your healthcare provider to determine if you need treatment.