The thoracic outlet carries nerves, arteries, and veins. It is actually an opening at the lower front and side of the neck between two muscles. Vessels arise out of the chest cavity from the heart and nerves enter the outlet from the neck. The clavicle or collarbone lies above the nerves and vessels as they go into the upper extremity and body. Injury to the thoracic outlet can cause neck, shoulder, arm and hand symptoms. Thoracic outlet occurs more frequently in women.
Anatomy of the Thoracic Outlet
Muscles and bones form the thoracic outlet opening.
The thoracic outlet is a common area that causes compression of nerves and blood vessels outside of the spine. It is this compression that produces tingling and numbness in the hand and fingers. Shoulder and neck pain are frequent complaints with this condition.
Common Causes of Thoracic Outlet
There are many causes for the onset for this condition. The more common causes, though not limited to, include:
- Trauma – Motor vehicle crashes and falls are two frequent causes of onset. The neck and anterior shoulder muscles are suddenly put under stress and are injured.
- Repetition – Repetitive injury from factory work or sports puts stress on the muscles resulting in muscle strain.
- Anatomical – Abnormal development of the 7th cervical vertebra is another cause. During development, the vertebra produces a rudimentary or underdeveloped rib. This is called a “cervical rib.” This anomaly is present in about 1% of the population and is bilateral in 80% of this group. Abnormal or congenital development of the scalene muscles has occurred in the neck.
- Pregnancy – Postural changes with pregnancy and fluid retention have been cited as contributors to thoracic outlet problems.
- Weight Lifting – Symptoms occur from the over development or bulking of the muscles from this sport. It decreases the size of the thoracic outlet. This results in the compression of the nerves and vessels.
- Sleep Disorders – Sleeping with a poor pillow or mattress may alter neck and back mechanics contributing to compression at the thoracic outlet. Sleeping on the stomach should be avoided as this stresses and compresses the thoracic outlet.
- Weight Gain – Excessive weight contributes to those that are predisposed to the condition. Breast enlargement causing increased body weight or the addition of breast implants can stress the area.
There are three types of thoracic outlet conditions that confront your doctor.
These include the following:
- Non-specific – This is a combination of nerve and vascular involvement. The symptoms vary and are usually a chronic presentation to the doctor. This includes symptoms such as weak grip, numbness and tingling in ALL the fingers and pain or ache in the hand, shoulder and neck. In some cases, there can be an atrophy of the tissue at the base of the thumb. Severe cases can demonstrate a bluish discoloration of the hand. A common complaint is coldness of the hand as well as the arm getting fatigued easily when working above shoulder height. Those using a hair dryer will frequently complain that their arms and hands feel tired. The arm will get so weak it has to be dropped down to the side for a short time to let blood into the muscles and then the process begins all over again. Raising the arm above shoulder height for a few minutes decreases the blood flow causing the tiredness and weakness.
- Vascular Compression – Occurs when only the arteries or veins are involved. This cause is less frequent but is a very serious complication. Surgical consult must be made as soon as possible. Clots may form in the vessels.
- Nerve Compression – If the nerves are involved, muscle atrophy at the base of the thumb is characteristic. Surgical repair is necessary.
Treatment for Thoracic Outlet
Activities such as working on the computer or occupations requiring the shoulders to droop forward can contribute to thoracic outlet symptoms. Treatment can include a simple action such as maintaining good posture during the day. Weight control through proper diet is helpful. Physical therapy modalities can be helpful in most cases during the early symptomatic phase of the condition. Serious cases may need surgical intervention. Workplace postural changes must take place to reduce stressful repetition. Non-surgical treatment of the condition generally will not resolve the symptoms quickly. It will more than likely be a gradual process as posture improves and contributing factors are eliminated or modified. Chiropractic manipulation should be directed to the lower cervical and upper thoracic spine to improve spinal vertebral motion. Myofascial release to the taut muscles helps improve posture. Self-care with the use of exercise is the most important element in the care and treatment. Failure to comply with exercise recommendations will destine one to treatment failure and ongoing complaints. Patients with drooping shoulders and muscular weakness will benefit greatly from increasing strength to the muscles of the shoulder and thoracic outlet.
Exercises specifically designed for the condition are an absolute for successful care. The following exercises are helpful for care and treatment of the thoracic outlet:
The doctors at Coon Rapids Chiropractic Office have experience in the care and treatment of thoracic outlet syndrome.