What is Thoracic Outlet Syndrome?

Thoracic outlet syndrome (TOS) is actually a group of different disorders that affect the nerves running from the neck into the arms. True neurologic TOS is rare, usually occurring in adult women. It causes weakness, numbness, and muscle wasting in the hand. Arterial TOS only occurs on one side of the body and causes sensitivity to cold, numbness, and pain in the hands. Venous TOS can develop after prolonged limb exertion. Traumatic TOS may be caused by repetitive activity or trauma, causing pain and weakness. Disputed TOS primarily causes pain and weakness, believed to be caused by trauma to the brachial plexus nerves. Some physicians believe that disputed TOS does not exist.

Who gets Thoracic Outlet Syndrome?

Anyone can get thoracic outlet syndrome, but arterial and true neurologic TOS are both caused by congenital problems (problems present at birth). Often symptoms do not appear until later in life. The cause of venous TOS is unknown, but it affects men and women equally. Traumatic TOS is usually caused by repetitive activity or trauma.

How is Thoracic Outlet Syndrome diagnosed?

After taking the patient's history, a physician may perform a physical examination to try to reproduce the patient's symptoms. An electrodiagnostic exam, nerve conduction test, or a magnetic resonance imaging scan (MRI) may also be performed.

How is Thoracic Outlet Syndrome treated?

Physical therapy and other exercises can help strengthen muscles, and anti-inflammatory drugs may help treat the pain. Surgery is rare.

More Information

American College of Osteopathic Family Physicians
American Academy of Orthopaedic Surgeons 
National Institutes of Neurological Disorders and Stroke

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