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. Talk to your patients about TOS.

What are the causes?

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 tight 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. You may notice symptoms of thoracic outlet syndrome if your job requires continuous repetition of a movement, such as typing on a computer for extended periods, working on an assembly line, or stocking shelves and repeatedly lifting things above your head.

What are the symptoms?

The symptoms of thoracic outlet syndrome—as well as their intensity—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

Compression of one or more veins and arteries can results in symptoms such as: 

• Bluish discoloration of the hand
• Swelling or puffiness in the arm or hand
• Coldness of hands or fingers
• Throbbing lump near the collarbone (clavicle)
• Deep pain in the neck and shoulder region that may increase at night
• Arms and hands that are easily fatigued

How is it diagnosed?

• Because TOS doesn’t have unique symptoms, it can be difficult to diagnose. It is important to differentiate TOS from other conditions, such as carpal tunnel syndrome, shoulder tendinitis and a herniated cervical disc.
• A detailed health history and thorough physical examination are the most important components in establishing the diagnosis of TOS.
• Your doctor of chiropractic may also recommend x-rays, MRI (magnetic resonance imaging), laboratory tests, or a nerve conduction velocity test if he or she suspects TOS.

How is it treated?

• 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. A chiropractic treatment plan for TOS may include a mix of joint mobilization/manipulation, physical therapy modalities, home stretching exercises, and soft-tissue therapy.
• 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. Weight reduction can be helpful for obese patients. Patients should avoid sleeping on the stomach with arms above the head. They should also avoid repetitively lifting heavy objects.
• A home exercise program can be a very valuable aspect of any TOS treatment plan. Exercises should be performed slowly and carefully. Each position is taken to the point where a stretch is felt, but no pain. Patients should not bounce to increase the length of their stretches in any positions.
• Consult with your doctor of chiropractic prior to starting a new exercise program. He or she can help develop an individualized program and provide instruction on proper stretching technique.