Thoracic outlet syndrome (TOS) involves the neurovascular bundle of the neck and arms. Specifically, there is the brachial plexus (group of nerves) and the blood vessels. Symptoms occur when there is pressure on either of these structures as they pass from the neck down the arms.
Symptoms include neck, arm, and hand pain. Many people are awakened at night with hand numbness and tingling. In the morning, their hands are stiff and swollen. The symptoms are often brought on or made worse by working with the arms overhead.
This occurs for several reasons. The upward rotation and outward motion of the shoulder blade causes the pectoralis minor muscle to clamp down on the subclavian artery and brachial plexus just under the collarbone where the collarbone and shoulder joint meet.
Sometimes there are congenital fibrous bands that also put pressure on the neurovascular bundle. Congenital means it’s something you were born with. And in some people, there is an extra rib that can also apply pressure to these structures.
There is successful treatment possible for many patients. A physical therapist can help change the person’s posture enough to take pressure off these areas. The therapist can help manually stretch the muscles and any fibrous bands that might be involved. And the patient can be taught specific stretching exercises to lengthen the muscles as they cross over critical structures.
In rare cases, surgery can be done to remove the extra rib or release the fibrous bands compressing the neurovascular bundle.