Symptoms of thoracic outlet syndrome (TOS) vary based on type. They may become worse when you lift your arms overhead or put pressure on this area.

Neurogenic TOS symptoms

• Numbness or tingling. This may happen in the arm or fingers — often the ring finger and little finger.
• Aches and pain. These may happen in the head, face, neck, shoulder, arm or hand.
• Muscle changes. Muscles may feel weaker or look smaller — especially in the hand. The ring finger or little finger may curl in toward the hand and look like a claw.

Venous TOS symptoms

• Changes in skin color. Skin on the arm, hand or shoulder may become blue, gray or purple depending on your skin color.
• Pain and swelling. Your hand, arm or shoulder may ache, appear swollen and feel heavy. Also, the hand may tingle or feel numb.
• Popping veins. You may see large veins surface around the shoulder.

Arterial TOS symptoms

• Pulsing lump under the skin. You may feel this near the collarbone.
• Cold skin with a drop in pulse and change in color. Skin of the fingers, hands or arms may feel cold and appear to be drained of color. Also, the pulse may feel weak or absent. When the condition is severe, skin on the fingertips may darken in color or develop sores. This is called gangrene.
• Pain, tingling and weakness. Your hand, fingers or arm may ache, tingle or tire easily, especially during use.

When to see a doctor

See your healthcare professional if you regularly experience any of the symptoms of thoracic outlet syndrome.

When to seek emergency care

• Sudden arm swelling with a change in skin color. Skin may appear blue, gray or purple depending on your skin color. This may signal damage to a vein.
• Sudden severe hand pain or change in the fingers. Hand swelling may signal damage to a vein. Painful fingertips that appear purple or black or develop sores may be a sign of gangrene. Gangrene is a serious condition that can develop when the flow of blood is blocked to a certain area.
• Weak pulse with cold skin that appears to be drained of color. This may signal damage to an artery.
• Weak or visibly smaller hand or arm muscles. This may signal damage to the nerves.

Thoracic outlet syndrome often is caused by pressure on the nerves or blood vessels in the thoracic outlet. This is the area between the neck and shoulder. The cause of the pressure varies and can include:

• Differences in the body. Some people are born with an extra rib in the neck, above the first rib. The extra rib, known as a cervical rib, can press on nerves or blood vessels. Also, there may be a tight, thick band of tissue connecting the spine to the rib that causes pressure.
• Posture. How you hold your body can affect how much pressure is on the thoracic outlet. Drooping your shoulders or holding your head too far forward can put pressure on this area. Also, changes in posture that happen during pregnancy or when carrying a heavy bag over the shoulder can increase pressure on the nerves and vessels in the thoracic outlet.
• Repeating movements. Repeating the same arm movements for a job, sport or other daily activity can cause strain. Over time, this strain can damage the nerves and blood vessels of the thoracic outlet.
• Trauma. A traumatic event, such as a car accident, can cause changes inside the body that compress the thoracic outlet. As the body responds, injured tissues may swell or thicken. This process can put pressure on the nerves and vessels in this area and cause TOS.

Several factors can raise the risk of thoracic outlet syndrome, including:

• Sex assigned at birth. Women are more than three times as likely to be diagnosed with thoracic outlet syndrome than are men.
• Age. Thoracic outlet syndrome may occur at any age. But it is most commonly diagnosed in adults between ages 20 and 50.

Complications are health issues that can develop as a result of thoracic outlet syndrome. The type of thoracic outlet syndrome you have can affect what complications develop:

• Blood clots or aneurysms. These are a complication of arterial or venous TOS. When blood vessels are pinched, the arm may become swollen and painful and show a change in skin color. If this happens, seek medical care right away. You may need urgent treatment.
• Chronic pain or disability. This is a complication of neurogenic TOS. When the nerves are pinched over time, long-term damage can happen. Neurogenic TOS can be confused with other joint or muscle injuries. If symptoms don't get better, see your healthcare professional for testing.

Here are some tips to prevent TOS.

In general:

• Don't carry heavy bags over your shoulder. This can put pressure on the thoracic outlet.
• Exercise. Stretch daily, and do movements that keep your chest, neck and shoulders strong and flexible.
• Maintain a healthy weight. If you're been told to lose weight, doing so may help prevent or relieve symptoms of TOS.

If you're at risk of TOS:

• Avoid lifting heavy objects. This puts more strain on the thoracic outlet.
• Avoid repeating movements that cause strain. These movements can stress and possibly damage the nerves and blood vessels of the neck and shoulders.

Diagnosing thoracic outlet syndrome can be hard. Symptoms can vary greatly among people. Members of your healthcare team will likely ask you questions and give you a physical exam. Also, you may need imaging and other types of tests.

Imaging and nerve study tests

To confirm the diagnosis of thoracic outlet syndrome, you may need one or more of the following tests:

• Ultrasound. An ultrasound uses sound waves to create images of your body. It's often the first imaging test used to help diagnose thoracic outlet syndrome. This test may be used to see if you have venous or arterial thoracic outlet syndrome or other vascular conditions.
• X-ray. An X-ray can reveal an extra rib, known as a cervical rib. X-rays also can help to rule out other conditions that could be causing your symptoms.
• Computerized tomography (CT) scan. A CT scan uses X-rays to get cross-sectional images of your body. A dye may be injected into a vein to view the blood vessels in greater detail, known as CT angiography. A CT scan may identify the location and cause of blood vessel compression.
• Magnetic resonance imaging (MRI). An MRI uses radio waves and magnetic fields to create a detailed view of your body. An MRI may be helpful to determine the location and cause of blood vessel compression. Sometimes dye is injected to better see the blood vessels. An MRI may reveal differences in anatomy, such as a fibrous band connecting your spine to your rib or a cervical rib. These differences in anatomy may be the cause of your symptoms. A healthcare professional may place your head, shoulders and neck in different positions. This may allow for a better view of the blood vessels in your arm.

• Arteriography and venography. In these tests, a thin, flexible tube called a catheter is inserted through a small cut, often in your groin. During arteriography, the catheter moves through your major arteries. During venography, the catheter moves through your veins. The catheter is threaded to the affected blood vessels. Then a dye is injected to show X-ray images of your arteries or veins.

  Healthcare professionals can check to see if you have a compressed vein or artery. If a vein or artery has a clot, doctors can deliver medications through the catheter to dissolve the clot.

• Electromyography (EMG). During an EMG, a needle electrode is inserted through your skin into various muscles. The test checks the electrical activity of your muscles when they contract and when they're at rest. This test can determine if you have nerve damage.

Nonsurgical treatments may be effective, especially if your condition is found early. These treatments may include:

• Physical therapy (PT). This is the first line of treatment for neurogenic thoracic outlet syndrome. PT exercises strengthen and stretch your shoulder muscles to open the thoracic outlet. The exercises may improve your range of motion and posture. Done over time, PT exercises may take the pressure off the blood vessels and nerves in the thoracic outlet.
• Medicines. You may be prescribed anti-inflammatory medicines, pain medicines or muscle relaxants. These medicines can lessen swelling and pain and ease tight muscles. If there is a blood clot, you may need a blood-thinning medicine.
• Clot-dissolving medicine. If you have blood clots from venous or arterial thoracic outlet syndrome, you may be given medicine to dissolve the clots. The medicine, known as a thrombolytic, goes into your veins or arteries to dissolve the clots. After you have thrombolytics, your healthcare professional may prescribe medicines to prevent blood clots. These medicines are known as anticoagulants.
• Injections, also called shots. You may get injections of a local anesthetic, a medicine called onabotulinumtoxinA (Botox) or a steroid medicine to treat neurogenic thoracic outlet syndrome. These medicines can help lessen pain.

Surgery

Your care team may suggest surgery if nonsurgical treatments haven't worked or if your symptoms have become worse.

A surgeon trained in chest surgery or blood vessel surgery often does the procedure. Chest surgery is known as thoracic surgery. Blood vessel surgery is known as vascular surgery.

Thoracic outlet syndrome surgery, also called thoracic outlet decompression, has risks of complications. These include injury to the nerves in the area, known as the brachial plexus. Also, surgery may not fully ease your symptoms. Symptoms may only be partially eased or come back at a later time.

Surgery to treat thoracic outlet syndrome may be done in different ways. Methods may involve removing a muscle and part of the first rib to relieve pressure. Surgery to repair damaged blood vessels also may be needed.

In venous or arterial thoracic outlet syndrome, your surgeon may suggest treatments before thoracic outlet decompression. This treatment can include medicines to dissolve blood clots or procedures to remove blood clots or repair blood vessels. If a damaged artery needs to be replaced, this can be done with a section of an artery from another part of your body, known as a graft. Or an artificial graft may be used. If you're also having a first rib taken out, this may be done as part of other procedures.

If you're diagnosed with thoracic outlet syndrome, a physical therapist may tell you to do exercises at home. The exercises can strengthen and support the muscles around your thoracic outlet.

To support your shoulders and the muscles around the thoracic outlet:

• Keep good posture.
• Take frequent breaks at work to move and stretch.
• Keep a healthy weight.
• Create a work area that allows you to keep good posture and doesn't make symptoms worse.
• Gently massage your shoulders and thoracic outlet.
• Apply a heating pad to the area.
• Practice relaxation exercises such as deep breathing, meditation and stretching.

Symptoms of thoracic outlet syndrome can be like those of many other conditions. This can make TOS hard to diagnose. Many people live with thoracic outlet syndrome symptoms for years before they are diagnosed with the condition. Discuss your concerns with your healthcare team if your symptoms go on and a diagnosis hasn't been made.

You're likely to start by seeing a member of your care team. Or you may be referred to a doctor trained in blood vessel conditions or blood vessel surgery, known as a vascular surgeon.

Here's some information to help you prepare for your appointment.

What you can do

• Be aware of anything you need to do ahead of time. When you make the appointment, ask whether there's anything you need to do before you come in.
• Write down any symptoms you're having. Include any that don't seem related to the reason you scheduled the appointment. Be as specific and detailed as possible in describing your symptoms. Include what part of your body is affected and how the discomfort makes you feel.
• Write down key personal information. Include any physical traumas you've experienced, even if the injuries happened years ago. Traumas may include a car accident or work-related injury. Note any physical activities or movements you tend to repeat now or repeated in the past. These may include movements done for work, sports, hobbies or other recreational activities.
• List key medical information. Include other conditions for which you're being treated. Also include the names of all prescription and nonprescription medicines or supplements that you're taking.
• Take a family member or friend along. Someone who comes with you may remember something that you missed or forgot.
• Write down questions. Ask members of your care team to answer them.

Preparing a list of questions helps you make the most of your time. For thoracic outlet syndrome, some basic questions to ask include:

• What's the most likely cause of my symptoms?
• What kinds of tests do I need?
• What treatments are available, and which treatment do you recommend for me?
• How likely is it that nonsurgical treatments will improve my symptoms?
• If nonsurgical treatments aren't effective, is surgery an option?
• Is there anything I can do to prevent symptoms from coming back?
• Will I need to change my job?
• Do I need to limit or give up activities that may be causing my symptoms?
• If you're recommending weight loss, how much weight do I need to lose to help my symptoms get better?
• I have other health conditions. How can I best manage them with this condition?
• 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 healthcare professional will likely ask several questions, such as:

• When did you first notice your 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 your symptoms or make them better?
• What activities do you do at your job?
• Do you or did you play sports?
• What are your hobbies or the recreational activities you do most often?
• Have you been diagnosed or treated for any other medical conditions? When?
• Have you noticed a lack of color or a change in color in one or more of your fingers or your entire hand? Have you noticed 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 ibuprofen (Advil, Motrin IB, others). Your discomfort also may lessen if you keep good posture and avoid lifting heavy objects and repeating the movements that cause strain.