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Thoracic Outlet Syndrome


  • Thoracic outlet syndrome (TOS) is a condition that occurs when nerves or blood vessels are compressed (pinched) in the thoracic outlet. The thoracic outlet is the area between your collarbone and your first (top) rib. Nerves and blood vessels run through the thoracic outlet as they go from your chest out to your hands. TOS may occur on one or both sides of your body. TOS may be caused by an injury, a congenital problem, drooping shoulders, or repeated movements. You may have pain, numbness, tingling, and swelling. You may have a weak grip or weak hand muscles and your hand may get smaller.
  • TOS is diagnosed with a health history and physical exam. Your caregiver will check your symptoms and may order more tests. Treatment depends on the kind of TOS you have. Treatment may include pain medicines and physical therapy. It may also include medicines to prevent or treat blood clots, or surgery. Treatment can help relieve symptoms and improve the use of your arm or hand.


You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment.


  • You may have decreased movement of your arms. Scalene muscle injections may cause nerve damage. This can lead to arm pain and tingling. Surgery may not relieve your symptoms. You may have bleeding problems or an infection after surgery. Nerve and lung damage may occur. Your signs and symptoms may come back after treatment.
  • You may get a blood clot in your arm. This can cause pain and swelling, and it can stop blood from flowing where it needs to go in your body. The blood clot can break loose and travel to your lungs. A blood clot in your lungs can cause chest pain and trouble breathing. This problem can be life-threatening. ATOS can damage arteries, which may block the blood flow to the hand and lead to aneurysms. An aneurysm is swelling of part of a blood vessel. This can lead to chronic (long-term) pain. Aneurysms may cause similar signs and symptoms as TOS.
  • Without treatment, NTOS may cause permanent nerve damage. Without treatment, VTOS may cause chronic problems such as pain, swelling of the arm, and tiredness from exercise. Delayed treatment of ATOS can lead to a chronic pain syndrome.


Informed consent

is a legal document that explains the tests, treatments, or procedures that you may need. Informed consent means you understand what will be done and can make decisions about what you want. You give your permission when you sign the consent form. You can have someone sign this form for you if you are not able to sign it. You have the right to understand your medical care in words you know. Before you sign the consent form, understand the risks and benefits of what will be done. Make sure all your questions are answered.


You may be given any of the following:

  • Nonsteroidal anti-inflammatory (NSAID) medicine may decrease swelling and pain or fever. This medicine can be bought with or without a doctor's order. This medicine can cause stomach bleeding or kidney problems in certain people. If you take blood thinner medicine, always ask your primary healthcare provider if NSAIDs are safe for you. Always read the medicine label and follow the directions on it before using this medicine.
  • Blood thinners: This medicine helps prevent clots from forming in the blood. Clots can cause strokes, heart attacks, and death. Blood thinners make it more likely for you to bleed or bruise. Use an electric razor and soft toothbrush to help prevent bleeding.

Treatment options:

Ask your caregiver for more information about these and other treatments you may need:

  • Physical therapy: A physical therapist helps you with special exercises. These exercises help strengthen the muscles in your neck, shoulders, and back. This can help increase the amount of room in the thoracic outlet. These exercises can also help improve your posture.
  • Surgery: Surgery may relieve pressure on your nerves or blood vessels. Surgery may be done if medicine and exercise do not relieve your symptoms. During surgery, one or more ribs may be removed. The scalene muscles may be cut or removed. Fibrous bands in the thoracic outlet may be removed.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Learn more about Thoracic Outlet Syndrome (Inpatient Care)

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