The thoracic outlet is a small space between the collarbone (clavicle) and the first rib. Thoracic outlet syndrome (TOS) is a group of disorders that involve compression, injury, or irritation of the nerves, blood vessels, or veins in the thoracic outlet. This can cause pain in the shoulders and neck and numbness in the fingers.
The cause of the compression can vary and may include:
- Anatomical defects: Inherited defects present at birth, including a cervical rib-an extra rib located above the first rib-or an abnormally right fibrous band connecting the spine to the rib.
- Poor posture: Drooping the shoulders or holding the head in a forward position can cause compression in the thoracic outlet area.
- Trauma: A traumatic event, such as a car accident, can cause internal changes that then compress the nerves in the thoracic outlet.
- Repetitive activity: Doing the same activity over and over can wear on the body’s tissues.
Another cause is the carrying of heavy shoulder bags or briefcases. In some cases, your health care provider may not be able to determine the exact cause of symptoms.
What Are the Symptoms of TOS?
The symptoms of thoracic outlet syndrome, as well as the intensity of any symptoms, vary between individuals and depend on the location of the compression site. When nerves are compressed, signs and symptoms often include:
- Numbness or tingling in the neck, shoulder, arm, or fingers
- An ache in the arm or hand
- Weakening grip
- Difficulty with fine-motor tasks
Diagnosis and Treatment of TOS
TOS does not have unique symptoms and can be difficult to diagnose. A detailed history and thorough physical examination are the most important components in establishing the diagnosis of TOS. It is important for your provider to differentiate TOS from other conditions, such as carpal tunnel syndrome, shoulder tendinitis, and a herniated cervical disc, just to name a few of the many conditions that can cause signs and symptoms.
Patients should avoid prolonged positions that cause them to hold their arms out or overhead. For example, avoid sleeping with the arm extended up behind the head. It is also helpful to have rest periods at work to minimize fatigue. Patients should avoid sleeping on the stomach with arms above the head. They should also avoid repetitively lifting heavy objects.
In the vast majority of neurological TOS cases, a conservative, non-surgical approach to treatment is most effective, especially when the condition is diagnosed early.