Thoracic Outlet Syndrome
Condition
(TOS)
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.
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Causes
TOS may be due to:
- Defects in nearby structures
- Trauma
- Poor posture
Risk Factors
Your risk of TOS is raised if you have:
- An extra rib or 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 and other tests of the nerves
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.
Occupational Safety and Health Administration
The Nicholas Institute of Sports Medicine and Athletic Trauma
CANADIAN RESOURCES:
Canadian Centre for Occupational Health and Safety
Public Health Agency of Canada
Occupational Safety and Health Administration
The Nicholas Institute of Sports Medicine and Athletic Trauma
CANADIAN RESOURCES:
Canadian Centre for Occupational Health and Safety
Public Health Agency of Canada
References
- Fugate MW, Rotellini-Coltvet L, Freischlag JA. Current management of thoracic outlet syndrome. Curr Treat Options Cardiovasc Med. 2009 Apr;11(2):176.
- Povelson S, Povlsen B. Diagnosing thoracic outlet syndrome: current approaches and future directions. Diagnostics (Basel). 2018;8(1):pii E21.
- Thoracic outlet syndrome. Ortho Info—American Academy of Orthopaedic Surgeons website. Available at: http://orthoinfo.aaos.org/topic.cfm?topic=a00336.
- Thoracic outlet syndrome. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T115626/Thoracic-outlet-syndrome .
- Thoracic outlet syndrome. National Institute of Neurological Disorders and Stroke website. Available at: https://www.ninds.nih.gov/Disorders/All-Disorders/Thoracic-Outlet-Syndrome-Information-Page.
- Vanti C, Natalini L, Romeo A, Tosarelli D, Pillastrini P. Conservative treatment of thoracic outlet syndrome. A review of the literature. Eura Medicophys. 2007 Mar;43(1):55.
Contributors
- Daniel A. Ostrovsky, MD
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