Overview

Median arcuate ligament syndrome, also called MALS, happens when the band of tissue in the upper belly area presses on the artery that sends blood to the stomach, spleen and liver. This tissue is called the median arcuate ligament. The artery is called the celiac artery.

The median arcuate ligament creates a pathway between the chest and belly area for the body's main blood vessel, called the aorta. Typically, the ligament goes across the aorta. The celiac artery sits just below the arch.

But sometimes, the ligament or arteries may be out of place. The ligament may put pressure on the celiac artery and the network of surrounding nerves, called the celiac plexus. This pressure can cause the symptoms of MALS. The condition can cause serious stomach pain in some people.

MALS can occur in anyone, even children. Other names for MALS are:

  • Celiac artery compression syndrome.
  • Celiac axis syndrome.
  • Dunbar syndrome.

Treatment involves surgery to release pressure from the ligament on the artery and nerves.

Symptoms

Pressure on the celiac artery doesn't always cause symptoms. MALS symptoms are mainly caused by pressure on the nerves.

Symptoms of MALS include:

  • Stomach pain after eating or exercising.
  • The stomach pain gets better by leaning forward or backward or standing while eating.
  • Fear of eating food because of pain.
  • Unintended weight loss.
  • Bloating.
  • Diarrhea.
  • Nausea and vomiting.

When to see a doctor

There are many different causes of stomach pain. If your stomach pain continues despite home care, call your healthcare professional. You need a complete physical exam and tests to determine the specific cause.

If your stomach pain is bad and activity or movement makes it worse, call your healthcare professional immediately. Get medical help right away if your stomach pain occurs with:

  • Bloody stools.
  • Fever.
  • Nausea and vomiting that doesn't go away.
  • Severe tenderness when you touch your belly.
  • Swelling of the belly.
  • Yellowing of the skin or whites of the eyes, also called jaundice.

Sometimes upper stomach pain can be confused with chest pain. Sometimes chest pain can be due to a heart attack. Call 911 or emergency medical help if you have chest or upper stomach pain with or without any of the following symptoms:

  • Pressure, fullness or tightness in your chest.
  • Crushing or searing pain that spreads to your jaw, neck, shoulders, and one or both arms.
  • Pain that lasts more than a few minutes or gets worse with activity.
  • Shortness of breath.
  • Cold sweats.
  • Dizziness or weakness.
  • Nausea or vomiting.

Causes

The exact cause of median arcuate ligament syndrome, also called MALS, is not known.

Risk factors

Because the cause of MALS is poorly understood, the risk factors are unclear. Median arcuate ligament syndrome is more common in adults than in children. It also is more common among women than among men.

MALS also has been seen in identical twins, so genetics may play a role.

Some people have developed median arcuate ligament syndrome after pancreatic surgery or blunt injury to the upper stomach area.

Complications

A complication of median arcuate ligament syndrome, also called MALS, is long-term pain, especially after meals. The pain can lead to a fear of eating and significant weight loss. The pain and related depression or anxiety can greatly impact quality of life. MALS symptoms may be vague. The symptoms can be similar to those of other conditions. It may take some time to get an accurate diagnosis.

Dec. 13, 2024
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