Cervical outlet and thoracic outlet syndrome
Thoracic Outlet Syndrome (TOS) is pain, numbness, tingling, and/or weakness in the arm and hand due to pressure against the nerves or blood vessels that supply the arm. It is due to tight muscles, ligaments, bands, or bony abnormalities in the thoracic outlet area of the body, which lies just behind the collar bone. Pressure on the nerves is the problem more than 95% of the time, but occasionally the artery or vein is involved.
The most frequent complaints are numbness and tingling in the fingers; pain in the neck, shoulder, and arm; headaches in the back of the head; weakness of the arm and dropping things from the hand; worsening of the symptoms when elevating the arm to do such things as comb or blow dry one's hair or drive a car, and coldness and color changes in the hand. The symptoms are often worse at night or when using the arm for work or other activities.
This may be due to cervical rib, normal bone, muscles, and fibrous tissue.
TOS is most often produced by hyperextension neck injuries. Auto accidents that cause whiplash injuries, and repetitive stress in the workplace, are the two most common causes. Some of the occupations that we see causing TOS include, working on assembly lines, keyboards, or 10-key pads, as well as filing or stocking shelves overhead. In some people, symptoms develop spontaneously, without an obvious cause. An extra rib in the neck occurs in less than 1% of the population. People born with this rib, called a cervical rib, are 10 times more likely to develop symptoms of TOS than other people. However, even in people with cervical ribs, it usually requires some type of neck injury to bring on the symptoms.
Physical examination is most helpful. Common findings are tenderness over the scalene muscles, located about one inch to the side of the wind pipe; pressure on this spot causes pain or tingling down the arm; rotating or tilting the head to one side causes pain in the opposite shoulder or arm; and elevating the arms in the "stick-em-up" position reproduces the symptoms of pain, numbness, and tingling in the arm and hand. There is often reduced sensation to very light touch in the involved hand (this can only be detected in people with involvement on one side).
Diagnostic tests, such as EMG's or NCV's, may show non-specific abnormalities, but in most people with TOS, these tests are normal. Neck or chest x-rays may show a cervical rib. Loss of the pulse at the wrist when elevating the arm or when turning the neck to the side (Adson's sign), has been thought by some to be an important diagnostic sign. However, we find it unreliable because many normal people also lose their pulse in the same positions, and the majority of people with TOS do not lose their pulse in these positions. Shrinkage of hand muscles (atrophy) occurs in about 1% of people with TOS, and these people will have nerve tests that show a typical pattern of ulnar nerve damage. Compression usually occurs when the arm is abducted.
Treatment begins with physical therapy and neck stretching exercises. Abdominal breathing, posture correction, and nerve glides, carried out on a daily basis, are a part of the therapy program. Gentle, slow movements and exercises are stressed. Methods like Feldenkrais have helped many people with TOS. Modalities to avoid are those that emphasize strengthening exercises, heavy weights, and painful stretching. It is important to be examined and tested for other causes of these symptoms because other conditions can coexist with TOS, and these should be identified and treated separately. Some of these associated conditions include carpal tunnel syndrome, ulnar nerve entrapment at the elbow, shoulder tendinitis and impingement syndrome, fibromyalgia of the shoulder and neck muscles, and cervical disc disease. Surgery can be performed for TOS, but it should be regarded as a last resort. Non-surgical forms of treatment should always be tried first.
Surgical resection of the first rib or fibrous band is controversial.
Are you a Doctor, Pharmacist, PA or a Nurse?
Join the Doctors Lounge online medical community
Editorial activities: Publish, peer review, edit online articles.
Ask a Doctor Teams: Respond to patient questions and discuss challenging presentations with other members.