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Thoracic outlet syndromeBy Mayo Clinic staff
Original Article: http://www.mayoclinic.com/health/thoracic-outlet-syndrome/DS00800
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Thoracic outlet syndrome is a group of disorders that occur when the blood vessels or nerves in the thoracic outlet — the space between your collarbone and your first rib — become compressed. This can cause pain in your shoulders and neck and numbness in your fingers.
Common causes of thoracic outlet syndrome include physical trauma from a car accident, repetitive injuries from job- or sports-related activities, certain anatomical defects, such as having an extra rib, and pregnancy. Even a long-ago injury can lead to thoracic outlet syndrome in the present. Sometimes doctors can't determine the cause of thoracic outlet syndrome.
Treatment for thoracic outlet syndrome usually involves physical therapy and pain relief measures. Most people improve with these conservative approaches. In some cases, however, your doctor may recommend surgery.
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Generally, there are three types of thoracic outlet syndrome.
- Neurogenic (neurological) thoracic outlet syndrome. This form of thoracic outlet syndrome is characterized by compression of the brachial plexus. The brachial plexus is a network of nerves that come from your spinal cord and control muscle movements and sensation in your shoulder, arm and hand. In the majority of thoracic outlet syndrome cases, the symptoms are neurogenic.
- Vascular thoracic outlet syndrome. This type of thoracic outlet syndrome occurs when one or more of the arteries and veins under the collarbone (clavicle) are compressed.
- Nonspecific-type thoracic outlet syndrome. This is also called disputed thoracic outlet syndrome or common thoracic outlet syndrome. Some doctors don't believe it exists, while others say it's a common disorder. People with nonspecific-type thoracic outlet syndrome have chronic pain in the area of the thoracic outlet that worsens with activity, but the specific cause of the pain can't be determined.
Thoracic outlet syndrome symptoms can vary, depending on which structures are compressed. When nerves are compressed, signs and symptoms of neurological thoracic outlet syndrome often include:
- Wasting in the fleshy base of your thumb (Gilliatt-Sumner hand)
- Numbness or tingling in your fingers
- Pain in your shoulder and neck
- Ache in your arm or hand
- Weakening grip
Signs and symptoms of vascular thoracic outlet syndrome — compression of one or more of your veins and arteries — can include:
- Discoloration of your hand (bluish color)
- Blood clot under your collarbone (subclavian vein thrombosis)
- Arm pain and swelling, possibly due to blood clots
- Throbbing lump near your collarbone
- Lack of color (pallor) in one or more of your fingers or your entire hand
- Weak or no pulse in the affected arm
- Tiny, usually black spots (infarcts) on your fingers
When to see a doctor
See your doctor if you consistently experience any of the signs and symptoms of thoracic outlet syndrome.
In general, the cause of thoracic outlet syndrome is compression of the nerves and blood vessels in the thoracic outlet, just under your collarbone (clavicle). The cause of the compression varies and can include:
- Anatomical defects. Inherited defects that are present at birth (congenital) may include a cervical rib — an extra rib located above the first rib — or an abnormally tight fibrous band connecting your spine to your rib.
- Poor posture. Drooping your shoulders or holding your 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. The onset of symptoms related to a traumatic accident often is delayed.
- Repetitive activity. Doing the same thing over and over can, over time, wear on your body's tissue. You may notice symptoms of thoracic outlet syndrome if your job requires you to repeat a movement continuously, such as typing on a computer for extended periods, working on an assembly line or repeatedly lifting things above your head, as you would if you were stocking shelves. Athletes, such as baseball pitchers and swimmers, also can develop thoracic outlet syndrome from years of repetitive movements. If you repeatedly carry heavy loads low on your body (rather than against your chest), you may also notice signs and symptoms of thoracic outlet syndrome.
- Pressure on your joints. Obesity can put an undue amount of stress on your joints, as can carrying around an oversized bag or backpack.
- Pregnancy. Because joints loosen during pregnancy, signs of thoracic outlet syndrome may first appear while you're pregnant.
Thoracic outlet syndrome left untreated can cause permanent nerve damage; however, surgery to treat thoracic outlet syndrome is considered risky. This is because the procedure involves dividing a muscle in the neck and removing a portion of the first rib or repairing the brachial plexus nerves. For this reason, most doctors initially recommend a conservative treatment approach.
Preparing for your appointment
You're likely to start by seeing your family doctor or a general practitioner. In some cases, your doctor may refer you to a doctor who specializes in vascular conditions or vascular surgery.
Here's some information to help you prepare for your appointment.
What you can do
- Be aware of any pre-appointment restrictions. When you make the appointment, ask if there's anything you need to do before you arrive at the office.
- Write down any symptoms you're experiencing, including any that seem unrelated to the reason for which you scheduled the appointment. Be as specific and detailed as possible in describing your symptoms, including what part of your body is affected and what adjectives you'd use to describe your discomfort.
- Write down key personal information, including any physical traumas such as a car accident or work-related injury. Even if they occurred years ago, your doctor will want to know about them. Also note any repetitive physical activities that you've performed — now or in the past — at work, in sports, and for hobbies and other recreational activities.
- List your key medical information, including other conditions you're being treated for and the names of any prescription and over-the-counter medications or supplements that you're taking.
- Take a family member or friend along, if possible. Someone who accompanies you may remember something that you missed or forgot.
- Write down questions to ask your doctor.
Preparing a list of questions will help you make the most of your time with your doctor. For thoracic outlet syndrome, some basic questions to ask your doctor include:
- What is likely causing my symptoms or condition?
- Are there any other possible causes for my symptoms or condition?
- What kinds of tests do I need?
- What treatment approach do you recommend?
- How likely are nonsurgical treatments to improve my symptoms?
- If conservative treatments aren't effective, is surgery an option?
- Is there anything I can do to prevent a recurrence of this problem?
- Will I need to change my job?
- Do I need to limit or give up other activities that may be causing my symptoms?
- If you're recommending weight loss, how much weight do I need to lose to notice an improvement in my symptoms?
- I have other health conditions. How can I best manage them with this condition?
- Should I see a specialist?
- Are there any brochures or other printed material that I can take home with me? What websites do you recommend visiting?
Don't hesitate to ask any other questions you have.
What to expect from your doctor
Your doctor is likely to ask you a number of questions, such as:
- When did you begin experiencing symptoms?
- How would you describe your symptoms?
- Have your symptoms changed over time?
- Where does your pain seem to start and where does it go from there?
- Does the pain or numbness worsen when you lift your arms overhead?
- Does anything else seem to worsen or improve your symptoms?
- What activities do you perform on your job?
- Do you or did you play sports?
- What are your hobbies or most frequent recreational activities?
- Have you been diagnosed or treated for any other medical conditions? When?
- Have you noticed a lack of color or a blue color in one or more of your fingers or your entire hand or other changes to the area?
What you can do in the meantime
While you're waiting for your appointment, try taking a nonsteroidal anti-inflammatory drug (NSAID), such as aspirin or ibuprofen (Advil, Motrin, others). Your discomfort also may be improved if you maintain good posture and avoid using repetitive movements and lifting heavy objects.
Tests and diagnosis
Diagnosing thoracic outlet syndrome can be difficult because the symptoms and their severity can vary greatly among people with the disorder. To diagnose thoracic outlet syndrome, your doctor may do a physical exam and ask about your medical history.
- Physical exam. Your doctor will perform a physical examination to look for external signs of thoracic outlet syndrome, such as a depression in your shoulder, a pale discoloration in your arm or limited range of motion.
- Medical history. Your doctor will also likely ask about your medical history and symptoms, as well as your occupation and physical activities.
Provocation tests are designed to reproduce your symptoms. The tests may help your doctor determine the cause of your condition, and also will help rule out other causes that may have similar symptoms.
Some of the more common provocation tests that can suggest the presence of thoracic outlet syndrome include:
- Adson's maneuver. For this test, you'll be asked to turn your head toward the symptomatic shoulder while you extend your arm, neck and shoulder slightly away from your body. While you inhale, your doctor will check for a pulse on the wrist of your extended arm. If your pulse is diminished or if your symptoms are reproduced during the maneuver, your doctor considers this a positive test result, which may indicate thoracic outlet syndrome. Because false-positives often occur, your doctor may repeat the test on the unaffected side.
- Wright test. From a sitting position and with the help of your doctor, you'll hold your arm up and back (hyperabduction), rotating it outward, while your doctor checks your pulse to see if it's diminished. As in the Adson's maneuver, your doctor will want to know if your symptoms are reproduced during the test.
- Roos stress test. From a sitting position, your doctor will ask you to hold both elbows at shoulder height while pushing your shoulders back. You will then repeatedly open and close your hands for several minutes. If your symptoms are present after the test, or if you feel heaviness and fatigue in your shoulders, this can indicate the presence of thoracic outlet syndrome.
Imaging and nerve study
To confirm the diagnosis of thoracic outlet syndrome, your doctor may also order one or more of the following tests:
- X-ray. Your doctor may order an X-ray of the affected area, which may reveal an extra rib (cervical rib) and can also rule out other conditions that may be causing your symptoms.
- Magnetic resonance imaging (MRI) scan. MRI is a painless procedure that uses a magnetic field and radio waves to create computerized images of the soft tissues of your body. These images can help your doctor determine the location and cause of compressions of the brachial plexus nerves or the subclavian artery. The scans may also reveal any congenital anomalies — such as a fibrous band connecting your spine to your rib or a cervical rib — that may be the cause of your symptoms.
- Electromyography (EMG). This test enables your doctor to see and hear how your muscles and nerves are working. To conduct the test, a small electrode needle is inserted through your skin and into the muscles near where you're having symptoms. The electrical activity detected by this electrode is displayed on a monitor and may be heard through a speaker.
- Nerve conduction study. Also called nerve conduction velocity, this test measures the speed of conduction of impulses through a nerve. Doctors use the test to evaluate possible nerve damage. Small electrodes are placed on your skin over the area being tested, and a tiny electrical current is sent to the nerves in your thoracic outlet. The electrical signals produced by nerves and muscles are picked up by a computer, and the information is interpreted by a doctor trained in electrodiagnostic medicine.
Treatments and drugs
In most cases, a conservative approach to treatment is effective, especially when the condition is diagnosed early. Treatment may include:
- Physical therapy. You'll learn how to do exercises that strengthen your shoulder muscles to open the thoracic outlet, improve your range of motion and improve your posture. These exercises, done over time, will take the pressure off your blood vessels and nerves in the thoracic outlet.
- Relaxation. Techniques that help you relax, such as deep breathing, can keep you from tensing your shoulders and remind you to maintain good posture.
- Medications. Your doctor may prescribe pain medications, muscle relaxants and anti-inflammatory drugs — aspirin or ibuprofen (Advil, Motrin, others) — to decrease inflammation and encourage muscle relaxation.
If conservative treatments don't improve your symptoms or if you're experiencing signs of significant nerve damage, worsening muscle weakness or incapacitating pain, your doctor may recommend surgery. Your doctor also may recommend surgery if you've been diagnosed with true neurogenic thoracic outlet syndrome, for which surgery is often the only treatment option, and for certain blood vessel complications, such as obstructed blood flow (occlusion) or ballooning of a portion of an artery (aneurysm) due to weakness in the wall of the blood vessel.
Surgery is usually effective in relieving pain associated with thoracic outlet syndrome. It may not be as successful in treating muscle weakness, especially if the condition has gone untreated for an extended period.
A specialist in thoracic surgery or vascular surgery will perform the procedure. All surgical options to treat thoracic outlet syndrome pose a significant risk of injury to the brachial plexus. The most common surgical approaches for thoracic outlet syndrome treatment are:
- Anterior supraclavicular approach. This approach repairs compressed blood vessels. Your surgeon makes an incision just under your neck to expose your brachial plexus region. He or she then is able to look for signs of trauma or may discover fibrous bands contributing to compression near your first (uppermost) rib and can repair any compressed blood vessels.
- Transaxillary approach. In this surgery, your surgeon makes an incision in your chest to access the first rib, then removes a portion of the first rib to relieve compression. The advantage of this type of surgery is that it gives the surgeon easy access to the first rib without disturbing the nerves or blood vessels. But it also means the surgeon has limited access to the area's nerves and vessels, and most fibrous bands and cervical ribs that may be contributing to compression are hidden behind these nerves and blood vessels.
Lifestyle and home remedies
If you're diagnosed with thoracic outlet syndrome, your doctor or physical therapist will instruct you on exercises to do at home to strengthen and support the muscles surrounding your thoracic outlet. In general, to avoid unnecessary stress on your shoulders and muscles surrounding the thoracic outlet:
- Maintain good posture
- Take frequent breaks at work
- Practice relaxation techniques
Coping and support
Symptoms associated with thoracic outlet syndrome can be caused by a number of other conditions, which makes it difficult for doctors to diagnose. Many people experience symptoms of thoracic outlet syndrome for years before they are diagnosed with the condition, which can cause stress and frustration.
Be sure to discuss your concerns with your doctor if your symptoms persist and a diagnosis hasn't been made. Getting a second opinion from another doctor may put your mind at ease and allow you to focus on getting better.
Thoracic outlet syndrome that goes untreated for years can cause permanent neurological damage, so it's important to deal with the symptoms early or, even better, to prevent the disorder altogether. If you're susceptible to thoracic outlet compression, avoid repetitive movements and lifting heavy objects. If you're overweight, you can prevent or relieve symptoms associated with thoracic outlet syndrome by losing weight.
Even if you don't have symptoms of thoracic outlet syndrome, avoid carrying heavy bags over your shoulder, because this can increase pressure on the thoracic outlet. Stretch daily, and perform exercises that keep your shoulder muscles strong.
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