Thoracic Outlet Syndrome (TOS)

Thoracic outlet syndrome (TOS) is a condition that causes pain, weakness, numbness, or other symptoms in your arm, hand, or fingers. It occurs when the nerves and blood vessels that run through the thoracic outlet—a small opening just below your collarbone—are pinched or blocked.

Some people are born with an extra rib or other skeletal condition that makes the thoracic outlet too narrow. Others develop TOS after an injury or because they use repetitive arm movements during work or play.

When left untreated, TOS can cause serious complications. And because TOS relatively rare but has symptoms that are similar to symptoms of other conditions, a skilled TOS specialist is often needed to diagnose it.

The vascular surgeons in the University of Iowa Heart and Vascular Center are among the few providers in the state with experience diagnosing and treating TOS.

Thoracic outlet syndrome symptoms

There are three different types of TOS. Each is named for the type of blood vessel or nerve affected, and each causes different symptoms.

Neurgoenic TOS

This is the most common type of TOS. It’s caused by compression of the nerves that control feeling and movement in your arms and hands. Symptoms include:

  • A feeling of tiredness in the arm, especially when you raise it
  • Arm or shoulder weakness
  • Pain, numbness, or tingling in your arm, hand, or fingers

Venous TOS

This type of TOS occurs when one of your major arm veins is compressed or blocked. It tends to cause:

  • Pain, tingling, or a bluish discoloration in your arm or hand
  • Swelling of your arm, hand, or fingers
  • Unusually swollen veins around the chest, neck, or shoulder

Arterial TOS

This is the rarest yet most serious form of TOS. It’s caused by a compressed artery. Symptoms may include:

  • A cold, pale hand
  • Pain in the arm or hand
  • Sores on the fingers, caused by poor blood circulation

Diagnosing thoracic outlet syndrome

If you have any TOS symptoms, you should ask for a referral to a vascular surgeon. Without proper diagnosis and treatment, TOS can cause blood clots, gangrene, or permanent arm pain or weakness.

To diagnose TOS, we need to rule out other common conditions that can cause arm pain and weakness. We use various tests—including nerve conduction studies, blood vessel ultrasounds, and MRI—to thoroughly assess your symptoms.

Thoracic outlet syndrome treatment offered by UI Heart and Vascular Center specialists

Treatments for TOS vary, depending on the type of TOS you have and the severity of your symptoms.

Nonsurgical treatments for TOS

For many people with neurogenic TOS, symptoms can be managed with nonsurgical treatments. These include:

  • Lifestyle changes: Your provider may ask you to lose weight, avoid repetitive arm motions, or change the layout of your workspace to promote better posture. These steps may help naturally expand the space in the thoracic outlet, reducing compression on your nerves.
  • Medicine: Anti-inflammatory medicines like ibuprofen or naproxen sodium can reduce pain and inflammation if you have mild TOS.
  • Physical therapy: Our physical therapists can teach you exercises to strengthen your shoulder and neck muscles, which helps stabilize your collarbone. They can also help you improve your posture while standing and sitting.

TOS surgery

If your symptoms are too advanced and nonsurgical treatments don’t help—or if you have venous or arterial TOS, which have a higher risk of complications—your provider may recommend surgery.

Different surgical procedures are used to treat different types of TOS. Our areas of expertise include:

  • Rib resection: If you were born with an extra rib, or if your first rib bone is narrowing your thoracic outlet space, your surgeon may remove part or all of it.
  • Scalenectomy: If certain neck muscles called scalene muscles compress your nerves or blood vessels, your surgeon may remove small pieces of those muscles. A scalenectomy is often performed with a rib resection.
  • Thrombolysis: This procedure gets rid of blood clots caused by arterial or venous TOS. Your surgeon will either dissolve the clot by injecting medication into your vein or break up the clot and suction it out using a special machine. When a thrombolysis is necessary, it’s usually performed before moving forward with a rib resection or scalenectomy.

Because the thoracic outlet affects so many important nerves, blood vessels, and other tissues in the neck and chest, it’s important to seek care from specialists who have experience performing TOS surgery.

UI Heart and Vascular Center surgeons are trained in these sophisticated techniques. They also help teach them to other surgeons. We’ve helped many teens and adults with TOS get rid of their symptoms and get back to full function.

Get a second opinion about your arm pain or weakness

Many medical conditions, including carpal tunnel syndrome, arthritis, and herniated discs, cause symptoms that mimic TOS.

If you’re being treated for one of these conditions and you still have pain, numbness, weakness, or swelling in your arm or hand, you should request a second opinion from the UI Heart and Vascular Center.

Our vascular surgeons frequently see people who were misdiagnosed or have not found relief elsewhere. We can help you confirm or rule out TOS and put you on the path to the right treatments and a complete recovery.

Need help finding a TOS specialist?

Call the UI Heart and Vascular Center for help finding a specialist with experience diagnosing and treating TOS.

Care Team