Arterial Thoracic Outlet Syndrome

    Learn more about our Patient Engagement products now! Turn your patients into active participants in their healthcare by giving them easy access to the same evidence-based information you trust – but delivered in an easy-to-understand format.

    Arterial Thoracic Outlet Syndrome

    Arterial Thoracic Outlet Syndrome

    The shoulder area, showing the top ribs, the clavicle, and the subclavian artery.

    Arterial thoracic outlet syndrome (TOS) is a condition that happens when the subclavian artery is squeezed or compressed. The subclavian artery is the artery that carries blood from the heart to the arm and hand. To reach the arm, this artery must pass through the thoracic outlet, which is a tight space under the collarbone (clavicle) and above the top rib. There are different types of TOS. The arterial type is the rarest.

    Depending on which structures are affected, you may have symptoms on one or both sides of your body.

    What are the causes?

    This condition is often caused by having a cervical rib. This is an extra rib at the base of your neck that presses on your subclavian artery. Over time, this pressure may cause a clot to form inside the artery, or the artery may weaken and balloon outward (aneurysm).

    What increases the risk?

    In addition to having a cervical rib, other factors can make you more likely to develop this condition. These include:
    • Being female.
    • Being overweight.
    • Poor posture.
    • A job or hobby that involves repeated movements with your arms over your head.
    • A history of Ehlers–Danlos syndrome.

    What are the signs or symptoms?

    Symptoms can affect one or both sides of the body. Symptoms include:
    • Pain and cramps in your arm or hand.
    • Pale skin or a change in color of the skin on your hand and arm.
    • Very cold hand or hands.
    • Weak pulses at your wrist.
    • Rarely, muscle loss in your hands.

    These symptoms may be worse when you hold your arms over your head.

    How is this diagnosed?

    This condition may be diagnosed based on:
    • Your symptoms and a physical exam. You may be asked to hold your arms over your head and in other positions to see if your symptoms get worse.
    • Tests to confirm the diagnosis and to find out the cause of your TOS. These may include:
      • X-rays to look for a cervical rib or another problem in the ribs.
      • An ultrasound. This test uses sound waves to create an image.
      • A CT scan.
      • An MRI scan.
      • An angiogram or venogram. In these tests, X-rays are done after a dye is injected into an artery or vein.
      • A pulse volume recording. This test measures the pulses in your wrists.

    How is this treated?

    This condition may be treated with surgery to:
    • Remove the cervical rib.
    • Remove a blood clot (thrombus).
    • Repair an aneurysm.

    Treatment may also include:
    • A procedure to open up the clotted artery and restore blood flow (angioplasty).
    • Medicine, including blood thinners or blood clot dissolvers.

    Follow these instructions at home:


    • If you are taking blood thinners:
      • Talk with your health care provider before taking aspirin or NSAIDs. These medicines can raise your risk of bleeding.
      • Take your medicines as told. Take them at the same time each day.
      • Do not do things that could hurt or bruise you. Be careful to avoid falls.
      • Wear an alert bracelet or carry a card that says you take blood thinners.
    • Take over-the-counter and prescription medicines only as told by your provider.


    • Do exercises as told by your provider or physical therapist.
    • Do not lift anything that is heavier than 10 lb (4.5 kg) until your provider says that it is safe.
    • Do not carry heavy bags over your shoulder or do repeated lifting of heavy objects over your head.
    • Take breaks often if you work at a keyboard or do other work that involves repeated movements of your hands and arms. Stretch and rest your arms during these breaks.

    General instructions

    • Stay at a healthy weight. Lose weight as told by your provider.
    • Maintain good posture.
    • Keep all follow-up visits. Your provider will check to see if your symptoms are improving with treatment.

    Contact a health care provider if:

    • You have pain, cramps, numbness, or tingling in your arm or hand.
    • Your arm or hand often feels tired.
    • Your arm turns a darker and different color than usual.
    • Your hand feels cold.
    • You have frequent headaches or neck pain.
    • You have muscle loss in your hand.

    Get help right away if:

    • You lose feeling in your arm or hand.
    • You cannot move your fingers.
    • Your fingers turn a dark color.

    This information is not intended to replace advice given to you by your health care provider. Make sure you discuss any questions you have with your health care provider.

    Small Elsevier Logo

    Cookies are used by this site. To decline or learn more, visit our cookie notice.

    Copyright © 2024 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

    Small Elsevier Logo
    RELX Group