Thoracic Outlet Syndrome (TOS)

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Thoracic outlet syndrome facts

  • Thoracic outlet syndrome is a condition whereby symptoms are produced from compression of nerves or blood vessels, or both, because of an inadequate passageway through an area (thoracic outlet) between the base of the neck and the armpit.
  • Symptoms include neck, shoulder, and arm pain, numbness, or impaired circulation to the extremities (causing discoloration).
  • Diagnosis of thoracic outlet syndrome is suggested by the symptoms and physical findings and is sometimes supported by electrical and/or radiology tests.
  • Treatment of thoracic outlet syndrome usually involves physical-therapy exercises and avoiding certain prolonged positions of the shoulder.

What is thoracic outlet syndrome?

Thoracic outlet syndrome is a condition whereby symptoms are produced (numbness in fingers , pain in shoulder and neck) by compression of nerves and/or blood vessels in the upper chest. The passageway for these nerves and blood vessels to exit the chest and supply the upper extremities is referred to as the thoracic outlet. Muscle, bone, and other tissues border the thoracic. Any condition that results in enlargement or movement of these tissues of or near the thoracic outlet can cause the thoracic outlet syndrome. These conditions include muscle enlargement (such as from weight lifting), injuries, an extra rib extending from the neck (cervical rib), weight gain, and rare tumors at the top of the lung. Often no specific cause is detectable.

It is felt by some researchers that the evolution of the torso of primates from a four-legged to a two-legged position may predispose humans to the development of thoracic outlet syndrome. The resulting vertical posture produced flattening of the chest cage and a shift of the shoulder joint backward, both of which narrowed the thoracic outlet.

Medically Reviewed by a Doctor on 1/23/2014

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Plumbing the Pits of Despair With Thoracic Outlet Syndrome

One patient's story

My symptoms started off somewhat vague. I had taken on a new position at work that required a lot of time on the computer. I began having pain on my right side in my neck and shoulder with tingling in my hand at the end of the day.