By Dr. Jihad Kudsi, double board-certified in General Surgery and Obesity Medicine
Some patients live for years with belly pain after eating, unexplained weight loss and a long list of normal test results. One rare cause is median arcuate ligament syndrome, or MALS. It is often missed because the symptoms overlap with many more common conditions. This guide explains what MALS is, how it is diagnosed, and how surgery can help. It is written for patients in Chicago and the western and southwestern suburbs.
What is median arcuate ligament syndrome?
The median arcuate ligament is a band of tissue near the diaphragm, at the top of the abdomen. In most people it sits above the celiac artery, a major vessel that supplies blood to the stomach, liver and other organs. In some people the ligament sits low and presses on the artery and on the nerves around it. This is called MALS, and it is also known as celiac artery compression syndrome or Dunbar syndrome.
Researchers still debate exactly why it causes pain. Possible explanations include reduced blood flow to the gut, irritation of the nerve tissue around the artery, or both. That uncertainty is one reason MALS is a diagnosis of exclusion, meaning other causes must be ruled out first.
Common symptoms
- Upper abdominal pain, often after eating
- Fear of eating because of the pain, and unintentional weight loss
- Nausea and vomiting
- Pain that can worsen with exercise
- Bloating or early fullness
MALS is more often reported in younger, thin women, but it can affect anyone. Many patients have seen several doctors and had multiple tests before the diagnosis.
How MALS is diagnosed
There is no single test. Diagnosis usually combines symptoms, imaging and the exclusion of other conditions:
- A careful history and exam, and tests to rule out gallbladder disease, ulcers, gastroparesis, pancreatitis and other GI conditions. Our gastroenterology and GI page covers some of these.
- Doppler ultrasound, often done during inhalation and exhalation, because the narrowing can change with breathing.
- CT or MR angiography, which can show the typical “hooked” appearance of the celiac artery.
- Sometimes a celiac plexus block, an injection that helps predict whether nerve-related pain might improve with surgery.
Findings on imaging alone do not confirm MALS. Some people have compression on a scan and no symptoms.
Treatment: median arcuate ligament release
For patients with a confirmed diagnosis and significant symptoms, the standard surgical treatment is to release the ligament so that it no longer presses on the artery. The surgeon may also treat the surrounding nerve tissue.
The operation is often done through small incisions using a laparoscopic or robotic approach. Compared with open surgery, this generally means less pain and a faster recovery. Learn more about our laparoscopic surgery of the GI tract and robotic surgery of the GI tract.
What results can patients expect?
Many patients report meaningful improvement in pain and weight after surgery, but not all do. Results depend on how carefully the patient was selected, how long symptoms have been present, and whether nerve involvement is a large part of the problem. A surgeon should discuss realistic expectations with you, including the chance that symptoms do not fully resolve.
Risks of surgery
As with any abdominal operation, risks include bleeding, injury to nearby structures, infection, and complications from anesthesia. Because the ligament sits close to major vessels, this operation is best done by a surgeon comfortable with delicate work in that area. Some patients need additional treatment for the artery if narrowing persists.
What recovery looks like
Most patients stay in the hospital briefly and return to normal activity over several weeks. Eating usually resumes in stages. Follow-up is important so that any persistent symptoms can be addressed.
When to see a specialist
Consider a specialist evaluation if you have:
- Chronic upper abdominal pain, especially after meals
- Unexplained weight loss
- A history of normal endoscopy, gallbladder and blood tests
- Symptoms that limit eating, work or exercise
Care near you
Dr. Kudsi evaluates patients with complex upper GI conditions at offices in Glen Ellyn and Oak Brook and at UChicago AdventHealth’s Bariatric and Obesity Medicine Clinic in LaGrange. Patients travel from Naperville, Hinsdale, Downers Grove and other Chicago suburbs. See our specialties page for an overview.
Frequently asked questions
Is MALS dangerous? It is not usually life-threatening, but it can seriously affect quality of life and nutrition.
Can MALS go away on its own? Symptoms can fluctuate, but the underlying compression does not usually resolve without treatment. Some patients manage symptoms with supportive care while they decide.
How is MALS different from other causes of abdominal pain? The pain is often triggered by meals and comes with weight loss, and imaging shows the celiac artery compressed. Because it is uncommon, it is usually diagnosed after other conditions are ruled out.
Do I need a special surgeon? An experienced surgeon with a strong understanding of upper abdominal anatomy is important. Ask how many MALS releases they have performed.
Schedule a consultation
If you think you may have MALS, book an online appointment or contact our office.
This article is for general education and does not replace medical advice.
