Definition

The thoracic outlet is the site of the lower neck and upper chest. It has a many nerves, blood vessels, muscles, and bones that run through a small site. Thoracic outlet syndrome (TOS) is when the nerves and blood vessels are squeezed, irritated, or harmed.

Thoracic Outlet Syndrome Copyright © Nucleus Medical Media, Inc.

Causes

TOS may be due to:

• Defects in nearby structures
• Trauma
• Poor posture
• Psychological factors

Risk Factors

Your risk of TOS is raised if you have:

• A first rib that is not typical
• Trauma
• Motions that you repeat often
• Job problems, such as poor posture or using the computer too much

Symptoms

TOS may cause:

• Arm or hand pain
• Lack of arm or hand strength
• Numbness and a feeling of pins and needles
• Cold sensitivity in the hands and fingers
• Pain or sores of the fingers
• Poor blood flow to the arm, hands, and fingers
• Swelling
• Skin of arm turning pale and blue

Diagnosis

Your doctor will ask about your symptoms and health history. A physical exam will be done.

Your doctor will ask you to hold your arms and head in positions that may cause TOS. The results of these tests will help show whether you have TOS.

You may also have:

• Blood tests
• Electromyography, other nerve conduction tests

Pictures may be taken with:

• Chest x-ray
• Ultrasound
• CT angiography
• MRI scan
• Venography

Treatment

Treatment depends on the symptoms that you have. In most cases, TOS is treated with pain medicine and physical therapy.

Prevention

TOS can’t be prevented.