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What is thoracic outlet syndrome?

Thoracic outlet syndrome (TOS) is the general term used to describe a condition caused by the compressing of the nerves and blood vessels between the neck and shoulders.


What are the occupational factors of thoracic outlet syndrome?

There are only a few studies indicating a relationship between manual work and thoracic outlet syndrome. However, work activities involving prolonged restricted postures such as carrying heavy shoulder loads, pulling shoulders back and down, or reaching above shoulder level can cause the inflammation and swelling of tendons and muscles in the shoulders and upper arms. When swollen or inflamed, they can compress the nerves and blood vessels between the neck and shoulders. Weak shoulder muscles, long necks and sloped shoulders, poor posture and obesity may contribute to thoracic outlet syndrome. Slightly more women than men may develop this syndrome.


What are the symptoms of thoracic outlet syndrome?

The symptoms of thoracic outlet syndrome include pain, arm and hand weakness, and numbness in the arm and fingers. In some cases, the sense of touch, or the ability to feel heat and cold may be lost.


How is thoracic outlet syndrome recognized?

The diagnosis is made by medical history and physical examination. Special laboratory tests can confirm the diagnosis.


How is thoracic outlet syndrome treated?

The initial treatment of patients with thoracic outlet syndrome consists primarily of a carefully planned program of exercise therapy. Avoidance of work activities suspected of causing the condition may be necessary. Physicians may prescribe anti-inflammatory drugs to reduce the pain and inflammation. In some cases surgery may be necessary if symptoms persist for a long time.


How can we prevent thoracic outlet syndrome?

The prevention of thoracic outlet syndrome should focus on the design or redesign of the workplace so that workers will avoid carrying heavy weights, reaching overhead, and lifting with the arms above shoulder level. Routine conditioning to strengthen muscles and improve posture can reduce pressure on nerves and blood vessels.

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Document last updated on January 2, 2009

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