What Is a Spinal Arteriovenous Malformation?

A spinal arteriovenous malformation (AVM) is an abnormal tangle of blood vessels in or near the spinal cord. In a healthy circulatory system, blood moves through tiny capillaries between arteries and veins. With an AVM, those normal connections do not form correctly.

Most spinal AVMs are thought to form before birth during blood vessel development. Problems can occur when abnormal vessels affect circulation, press on the spinal cord, or bleed into surrounding tissue.

This change in blood flow can place pressure on the spinal cord or reduce the oxygen reaching nearby nerves. Some spinal AVMs never cause symptoms, while others may lead to serious neurological problems over time.

Symptoms

Symptoms of a spinal AVM can develop slowly or appear suddenly if bleeding occurs. Some people may not notice symptoms until the condition has progressed.

Symptoms may include:

• Weakness in the arms or legs
• Difficulty walking
• Leg stiffness or muscle spasms
• Numbness or tingling
• Back pain or nerve pain
• Trouble with balance or coordination
• Loss of bowel or bladder control
• Paralysis in severe cases

How Is It Diagnosed?

Healthcare providers begin with a neurological exam and a review of symptoms. Imaging tests help show the location and size of the AVM.

Common tests include:

• MRI scans
• CT scans
• Magnetic resonance angiography (MRA)
• Spinal angiography to closely examine blood vessels

These tests help providers plan the safest and most effective treatment approach.

How Is It Treated?

Treatment depends on the size, location, and symptoms of the AVM. Some patients may only need monitoring, while others require more advanced treatment.

Treatment options may include:

• Medicines to help manage pain or muscle symptoms
• Endovascular embolization to reduce blood flow to the AVM
• Surgery to remove abnormal blood vessels
• Focused radiation therapy for selected cases
• Physical rehabilitation to improve strength and movement

Early treatment may help reduce the risk of bleeding and long-term spinal cord damage.