Thoracic Outlet Syndrome

Thoracic Outlet Syndrome (TOS) is caused by compression of nerves or blood vessels, or both, as a result of trauma, disease or congenital deformity in the thoracic outlet between the clavicle and first rib. Treatment begins with exercises to stretch and open the tissues associated with the thoracic outlet. If symptoms persist, surgery is an option. The surgeon makes an incision above the clavicle and removes scalene muscles, along with the first rib, easing pressure on the brachial plexus nerves. About 80 percent of patients experience complete resolution of symptoms; 20 percent report significant improvement.

What is TOS:
TOS affects the space between the collarbone and the first rib, where blood vessels and/or nerves in the area are compressed. There are three types of TOS:

  1. Arterial TOS is compression of the subclavian artery which causes decreased blood flow to the arm
  2. Venous TOS is compression the subclavian vein and can lead to swelling and venous clot formation
  3. Neurogenic TOS is compression of a group of nerves called the brachial plexus and can cause nerve damage, pain, and tingling in the arm and shoulder.

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