What is Thoracic Outlet Syndrome (TOS)?

The thoracic outlet is a small area between your collarbone, first rib and vertebra. Thoracic outlet syndrome (TOS) is a group of conditions characterized by compression of the nerves, arteries or veins in this space. Thoracic outlet syndrome can cause neck and shoulder pain, numbness and tingling of the fingers and a weak grip. If left untreated, TOS can lead to increased pain and decreased function. Certain forms of the disease can cause serious blood clots.

Thoracic outlet syndrome can be difficult to diagnose, as symptoms of it often mimic other disorders. Expert vascular specialists in the Division of Vascular and Endovascular Surgery at the Brigham and Women’s Heart & Vascular Center provide specialized diagnostic services to identify TOS as well as proven medical and surgical techniques designed for thoracic outlet syndrome treatment.

Thoracic Outlet Syndrome Information

Types of Thoracic Outlet Syndrome

Thoracic outlet syndrome can come in one of three types, all impacting different locations within the thoracic outlet. The nerves are most often affected as much as 95% of the time. Veins and arteries can also be affected by TOS. In each situation, the thoracic outlet gets compressed.

There are three types of thoracic outlet syndrome:

  • Neurogenic thoracic outlet syndrome. Nerve-related (neurogenic) involves compression of one or more brachial plexus nerves from the neck to the hands
  • Arterial thoracic outlet syndrome. Artery-related (arterial) involves compression of the subclavian artery as it exits the chest and travels to the arm
  • Venous thoracic outlet syndrome. Vein-related (venous) involves occlusion of the subclavian vein as it enters the chest cavity from the shoulder
What Causes Thoracic Outlet Syndrome?

Thoracic outlet syndrome causes range from an injury to poor posture. When the nerves, arteries and veins in the thoracic outlet get compressed, it can lead to TOS. The compression can come from a mix of injury types—sudden or repetitive—or be brought upon by several other situations, sometimes genetic and other times environmental. Some of the more common thoracic outlet syndrome causes:

  • Anatomical defects such as an extra rib
  • Injury to the back or neck
  • Obesity
  • Poor posture
  • Pregnancy
  • Repetitive injuries from lifting heavy loads
  • Sports that require repetitive arm motion or heavy lifting
  • Tumors that press on nerves

Can Poor Posture Cause Thoracic Outlet Syndrome?

The ramifications of poor posture extend to the thoracic outlet. Poor body alignment compresses the thoracic outlet between the collarbone and rib cage, limiting the space for nerves, arteries and veins. A drooping shoulder can also result in thoracic outlet syndrome.

Symptoms of Thoracic Outlet Syndrome

Symptoms of TOS vary depending upon whether the compression is related to nerves, arteries or veins. Differing types of thoracic outlet syndrome can yield symptoms of TOS anywhere from the neck and shoulder down through the arm and hand to the fingers. Patients may experience a mix of types of TOS syndrome, resulting in additional symptoms.

Nerve-related thoracic outlet syndrome symptoms:

  • Gilliatt-Sumner hand (severe wasting in the fleshy base of the thumb)
  • Numbness or tingling in your arm or fingers
  • Pain in your neck, shoulders or hands
  • Weak grip

Vein or artery-related thoracic outlet syndrome symptoms:

  • Bluish color to your hand
  • Swelling and pain in your arm
  • Blood clots in veins or arteries in the upper body
  • Lack of color in hand or fingers
  • Weak or no pulse in affected arm
  • Cold fingers, hands or arms (cold arm syndrome)
  • Fatigue in arm after activity
  • Numbness or tingling in fingers
  • Weakness of arm or neck
  • Throbbing lump near your collarbone
  • Padgett-Schroeder Syndrome—effort thrombosis of axillary vein

Does Thoracic Outlet Syndrome Cause Fatigue?

Pain is the leading thoracic outlet syndrome symptom, but arm fatigue can also present as a symptom, especially during activity.

Diagnosis of Thoracic Outlet Syndrome

Your vascular surgeon will often work in conjunction with a neurologist to evaluate your symptoms. Tests for thoracic outlet syndrome begin with a patient's medical history and a physical examination—including mobility testing—to understand pain points and determine if there is discoloration or swelling. Testing for thoracic outlet syndrome can include several diagnostic tests meant to rule out other conditions and pinpoint the location of the compression. When determining how to diagnose thoracic outlet syndrome, your health care provider may use a combination of tests and images in order to obtain the best results for diagnosis and treatment of thoracic outlet syndrome.

Common tests include:

  • Arteriography and venography tests to see if a vein or artery is compressed or has a clot
  • Electromyography (EMG) to measure electrical activity in muscles
  • Elevated arm stress test
  • Imaging tests, including X-ray, CT-scan and ultrasound
  • Nerve conduction study (NCS) to determine nerve damage and destruction
  • Thoracic outlet specific MRI of the chest

What Other Conditions Does Thoracic Outlet Syndrome Mimic?

Thoracic outlet syndrome mimics other conditions due to the location of the pain. Other conditions that need to be ruled out may include angina (heart issues caused by inadequate blood supply), rotator cuff injuries, fibromyalgia, cervical disc disorders, multiple sclerosis and tumors.

Treatment for Thoracic Outlet Syndrome

Specific treatment for thoracic outlet syndrome varies depending on the type of TOS. Common strategies include physical therapy, pain medications, lifestyle changes, thrombolytic therapy and surgery.

Specialists from the Brigham and Women’s Heart and Vascular Center develop individualized treatment plans for patients based on:

  • Age
  • Overall health
  • Medical history
  • Severity and form of the disease
  • Tolerance for specific medications or procedures
  • Expectations for course of the disease
  • Presence of other conditions

Specific treatment varies depending on the type of TOS and may include:

Neurogenic Thoracic Outlet Syndrome Treatment

  • Physical therapy offers a common first treatment
  • Pain medications, such as ibuprofen, stronger pain medications or muscle relaxants
  • Lifestyle changes including improved posture, avoiding strenuous activities, avoiding repetitive activities and weight loss
  • Surgery is a final option if physical therapy and lifestyle changes don't alleviate symptoms. Surgery can include cutting muscles or removing the cervical (first) rib

Arterial Thoracic Outlet Syndrome Treatment

  • Medication (blood thinners) to treat clots
  • Surgery is commonly recommended and may require cutting muscles or removing the cervical rib, repairing arteries and rerouting blood around the compressed area or angioplasty

Venous Thoracic Outlet Syndrome Treatment

  • Medications to thin the blood and treat clots
  • Thrombolytic therapy to dissolve clots
  • Surgery may require cutting muscles or removing the cervical rib, repairing veins and arteries and rerouting blood around the compressed area or angioplasty

When is Thoracic Outlet Syndrome Surgery Needed?

Thoracic outlet syndrome surgery is most common for arterial TOS but may be needed in other types, especially venous TOC. When physical therapy, medication and other therapies cannot relieve the compression or clotting in the thoracic outlet, surgery can create additional space in the area or repair blocked or damaged arteries and veins.

How to Prevent Thoracic Outlet Syndrome

If you're at risk for TOS, you can prevent exacerbating thoracic outlet syndrome with a mixture of lifestyle changes.

  • Daily neck and shoulder stretching can improve muscle strength
  • Good posture reduces the risk of compression
  • Avoiding lifting heavy objects over your shoulder decreases the risk of pressure on the thoracic outlet
  • Losing weight may relieve symptoms if you are overweight
  • Avoiding repetitive movements that place strain on the thoracic outlet

What to Expect at the Heart & Vascular Center

The Heart & Vascular Center is located in the Shapiro Cardiovascular Center, across the street from Brigham and Women’s main 75 Francis St. entrance. The Heart & Vascular Center brings together the full range of services in one location, fostering seamless and coordinated care for all cardiovascular patients.

If you are having surgery or a procedure, you will likely be scheduled for a visit to the Watkins Clinic for pre-operative information and tests.

The day of surgery, your care will be provided by surgeons, anesthesiologists and nurses who specialize in surgery for patients with thoracic outlet syndrome. After surgery, you will go to the post-surgical care unit, where you will receive comprehensive care from an experienced surgical and nursing staff.

During your surgery, family and friends can wait in the Shapiro Family Center. Staff members will provide surgery updates and caregivers who leave the hospital will be contacted by cell phone.

Multidisciplinary Care

Patients benefit from the teamwork of vascular and endovascular surgeons who collaborate with colleagues in other medical specialties. They work alongside nurses, physician assistants, physical therapists, dietitians and social workers to achieve outstanding outcomes for our patients.

Additional Resources

Learn more about Brigham and Women's Hospital

For over a century, a leader in patient care, medical education and research, with expertise in virtually every specialty of medicine and surgery.

About BWH