Thoracic Outlet Syndrome | Symptoms, Causes, & Types | MedStar Health
MedStar Health has a comprehensive and effective approach to treating thoracic outlet syndrome.

Relieving the pressure at MedStar Health

Thoracic outlet syndrome (TOS) involves pinching and compression of the nerves and blood vessels in the space between the collarbone and the first rib. The doctors in our Vascular and Endovascular Program are recognized leaders in treating patients with disorders such as this, and we’re on the forefront of the most advanced treatment techniques available.

TOS can cause swelling, discoloration, weakness, numbness, or pain in the shoulder, arm, and fingers. Sports that involve repeated shoulder movement, such as baseball or swimming, may increase your risk. You may also be at risk due to an injury to your back or neck, poor posture, or defects present from birth.

There are various types of TOS, including axillo-subclavian vein thrombosis. Without proper treatment, the condition can lead to serious problems, including death of tissue (gangrene), blood clots, or a pulmonary embolism.


Thoracic outlet syndrome can be a result of an extra rib (cervical rib), an accessory (extra) muscle, or scar tissue from trauma, fracture of the clavicle (collarbone), or repetitive use that reduces the space for the vessels and nerves.

In addition, these factors may increase your chances of developing thoracic outlet syndrome:

  • Congenital abnormalities or birth defects, resulting in bony and soft tissue abnormalities

  • Repetitive activities that can result in injuries from overuse (i.e., assembly line work, typing, overhead reaching, carrying heavy shoulder loads, etc.)

  • Injury to the neck or back (i.e., whiplash injury or overstretching)

  • Sleep disorders

  • Tumors or large lymph nodes in the upper chest or underarm area

  • Stress or depression

  • Participating in sports that involve repetitive arm or shoulder movement, such as baseball, swimming, golfing, and volleyball

  • Poor posture

  • Weightlifting

  • Motor vehicle crashes


The most common symptoms of thoracic outlet syndrome are:

  • Numbness and tingling of the fingers or in the arm

  • Pain in the shoulders, neck, and arms

  • Pain around the collarbone region

  • Impaired circulation to the affected areas

  • Muscle spasms in the scapular area or upper back, the area between the base of the neck and the shoulders

  • Wasting in the fleshy base of your thumb (Gilliatt–Sumner hand)

  • Weakness of the arm and hand with weakening of hand grip on the affected side

  • Symptoms become worse with repetitive or overhead activities

  • Swelling of the affected arm

  • Blue or discolored fingers

  • Bulging or pulsating mass below the collarbone


Depending on the type of thoracic outlet syndrome, our approach can be to recommend a combination of physical therapy, medication, and when appropriate, weight loss, as a first line of defense before surgery. 

For patients who do not find relief from this approach, surgery may be the answer. Patients who receive surgery usually have excellent results. In cases of arterial and venous thoracic outlet syndrome (TOS), surgery is the standard of care.

The first and most important step is getting a good diagnosis. Common diagnostic tests and procedures can include:

  • Physical exam looking for signs of TOS
  • Nerve conduction studies to evaluate the function of the motor and sensory nerves
  • Vascular studies of the arteries or veins
  • Chest X-ray to rule out cervical rib abnormalities
  • Cervical spine X-rays to rule out a cervical rib (extra rib) or cervical spine (neck) abnormalities
  • Computed tomography (CT) scan and magnetic resonance imaging (MRI) of the chest
  • CT scan or MRI of the spine to rule out cervical spine impingement or pressure, which can mimic neurogenic thoracic outlet syndrome
  • Magnetic resonance imaging with angiography (MRA) to view blood vessels
  • Angiogram/venogram, an X-ray that is taken as a special dye is injected to look at blood flow
  • Blood tests

Why choose us for your thoracic care?

A strong team

We have assembled the region’s largest team of fellowship-trained thoracic surgeons who provide treatment for the full array of benign and malignant lung, esophageal, and general thoracic diseases in adolescent and adults.  

Delivering tailored care

Our multidisciplinary care team provides an expanse of consultative, diagnostic, and surgical treatments and knowing when to employ those techniques enables our patients to have highly individualized treatment plans and excellent outcomes. 

Leaders in innovative technologies

We pride ourselves on being at the forefront of thoracic operative technology including robotic surgery while maintaining the expertise and capability of traditional surgery.  


Arterial thoracic outlet syndrome (ATOS)

Neurogenic thoracic outlet syndrome (NTOS)

Tracheobronchial malacia

Venous thoracic outlet syndrome (VTOS)


Physical therapy and medications may help relieve your symptoms and reduce your risk of a dangerous blood clot. If these approaches aren’t enough, you may need a surgical procedure called thoracic outlet decompression.

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Our Providers

Our doctors are recognized leaders in treating patients with thoracic disorders, and are on the forefront of the most advanced treatment tec ...

Our locations

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MedStar Franklin Square Medical Center

9000 Franklin Square Dr.
Baltimore, MD 21237

MedStar Good Samaritan Hospital

5601 Loch Raven Blvd.
Baltimore, MD 21239

MedStar Harbor Hospital

3001 S. Hanover St.
Baltimore, MD 21225

MedStar Union Memorial Hospital

201 E. University Pkwy.
Baltimore, MD 21218

MedStar Montgomery Medical Center

18101 Prince Philip Dr.
Olney, MD 20832

MedStar Southern Maryland Hospital Center

7503 Surratts Rd.
Clinton, MD 20735

MedStar St Mary's Hospital

25500 Point Lookout Rd.
Leonardtown, MD 20650

MedStar Georgetown University Hospital

3800 Reservoir Rd. NW
Washington, DC, 20007

MedStar Washington Hospital Center

110 Irving St. NW
Washington, DC 20010

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