Elsevier – Patient Education │Arterial Thoracic Outlet Syndrome

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, and 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 may be 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?

The following factors may make you more likely to develop this condition:

Having been born with a cervical rib.
Being overweight.
Having poor posture.

What are the signs or symptoms?

Symptoms of this condition 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 hands.
Muscle loss in your hands. This is rare.

These signs and 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. Your health care provider may ask you to hold your arms over your head and in other positions to check whether your symptoms get worse.
Tests and imaging studies to confirm the diagnosis and to find out the cause of your TOS. These tests may include:
- X-rays to look for a cervical rib or another abnormality of 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 vein and restore blood flow (angioplasty).
Medicine, including blood thinners or blood clot dissolvers.

Follow these instructions at home:

Medicines

If you are taking blood thinners:
- Talk with your health care provider before you take any medicines that contain aspirin or NSAIDs, such as ibuprofen. These medicines increase your risk for dangerous bleeding.
- Take your medicine exactly as told, at the same time every day.
- Avoid activities that could cause injury or bruising, and follow instructions about how to prevent falls.
- Wear a medical alert bracelet or carry a card that lists what medicines you take.
Take over-the-counter and prescription medicines only as told by your health care provider.

Activity

Do exercises as told by your health care provider or physical therapist.
Do not lift anything that is heavier than 10 lb (4.5 kg), or the limit that you are told, until your health care provider says that it is safe.
Do not carry heavy bags over your shoulder or repetitively lift heavy objects over your head.
Take breaks often to stretch and rest your arms if you work at a keyboard or do other repetitive work with your hands and arms.

General instructions

Maintain a healthy weight. Lose weight as told by your health care provider.
Maintain good posture.
Keep all follow-up visits as told by your health care provider. This is important.

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.

Summary

Arterial thoracic outlet syndrome (TOS) is a condition that happens when the subclavian artery is squeezed or compressed. This artery carries blood from the heart to the arm and hand.
This condition may be caused by having a cervical rib, which is an extra rib at the base of your neck that presses on your subclavian artery.
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 hands, and muscle loss in your hands.
This condition may be treated with surgery, a procedure to restore blood flow (angioplasty), or medicines.