Thoracic Outlet Syndrome

1 What is Thoracic Outlet Syndrome?

When the blood vessels or nerves in between the collarbone and the first rib are compressed, a group of disorders occur called Thoracic Outlet Syndrome.

It is a common cause of pain in shoulder and numbness of fingers. Causes may range from physical trauma to pregnancy.

Treatment requires in this case may be physiotherapy, pain relief medications and surgery.

2 Symptoms

Signs and symptoms of thoracic outlet syndrome vary depending on its cause.

There are three types of thoracic outlet syndrome depending on the weather blood vessels got compressed or nerves are compressed.

The first type is Neurogenic thoracic outlet syndrome

It is characterized by compression of brachial plexus which is a network of nerves controlling muscles movements and sensation in shoulder, arm and hand. Signs and symptoms of neurogenic thoracic outlet syndrome include:

  • wasting in the fleshy base of the thumb (Gilliatt-Sumner hand),
  • numbness or tingling sensation in arm or fingers,
  • pain in neck,
  • shoulder or hand and weakening grip.

The second type is Vascular thoracic outlet syndrome

In which one or more blood vessels under the collar bone are compressed. Signs and symptoms include:

  • Discoloration of hand,
  • arm pain and swelling,
  • blood clot in veins or arteries in upper areas of the body,
  • pale color of one or more fingers or entire hand,
  • weak pulse in the affected arm,
  • cold fingers or arm,
  • arm weakness,
  • numbness in fingers
  • and throbbing lump near the clavicle (collarbone).

The last type is nonspecific-type thoracic outlet syndrome

Which is quite controversial since some doctors say it doesn’t exist while other say that it is a common disorder. People with this disorder experience chronic pain and inactivity.  

3 Causes

The cause of thoracic outlet syndrome is compression of nerves or blood vessels in the space between collar bone and 1st rib.

The following are causes of compression:

  • Anatomical defects: Congenital defects like presence of extra rib or abnormally tight fibrous band may lead to compression.
  • Poor posture: Drooping shoulders or holding the head in forward position may lead to this disorder.
  • Trauma: A car accident can cause internal changes leading to compression of nerve-vessel bundle.
  • Repetitive activity: Doing same activity over and over again may lead to wear and tear of body tissues which can lead to this disorder.
  • Pressure on joints: Obesity, carrying an oversized bag or backpack may put extra pressure on shoulder joint.
  • Pregnancy: Joints loosen up during pregnancy leading to appearance of the symptoms of thoracic outlet syndrome.

4 Making a Diagnosis

Diagnosis of thoracic outlet syndrome is difficult because symptoms vary depending on the type and severity of the disease.

The following diagnostic methods are used:

Physical examination

Doctor will perform physical examination to look for

  • depression in shoulder,
  • swelling or pale discoloration in arm,
  • abnormal pulse
  • and check range of motion.

History of illness also helps in diagnosis of the condition effectively.

Provocation tests

In this doctor asks to move arms, neck or shoulders in various positions. Doctor will assess symptoms by examining patient in different positions.

Imaging and nerve study tests

X- ray of the affected area which will reveal the presence of extra rib. Ultrasound can be helpful to identify vascular thoracic syndrome and other vascular syndromes. Computerized tomography a dye may be injected into vein to view blood vessels in greater detail.

Magnetic resonance imaging can be used to locate and cause blood vessel compression. MRI may also reveal congenital anomalies. Magnetic resonance imaging is most commonly used diagnostic test used to diagnose thoracic outlet syndrome.

Arteriography and venography is done by inserting a thin tube through small incision through the groin and the catheter is moved through major arteries. The doctor injects a dye through the catheter to show x-ray images.

Electromyography is a procedure in which the doctor inserts a needle electrode through skin into various muscles and electrical activity of muscles is tested.

Nerve conduction study is a study used to evaluate the nerves ability to send impulses to muscles in different areas of the body.  

5 Treatment

Conservative therapy is opted to treat thoracic outlet syndrome.

Additional treatment options may include:

Physical therapy

Neurothoracic outlet syndrome can be treated with physical therapy by performing some exercises and improving the range of motion.


Anti-inflammatory medications such as

  • Ibuprofen,
  • analgesics,
  • fibrinolytic
  • and muscle relaxants are given to relieve the symptoms.

Surgical procedures

If conservative therapy is not effective, surgery is recommended. Thoracic outlet syndrome surgery has many complications and may not relive symptoms completely.

Following are the surgical procedures

Transaxillary approach in which an incision is made near the 1swt rib and remove portion of rib to relieve compression. Supraclavicular approach is used to repair compressed blood vessels. Surgeon makes an incision under the neck to expose brachial plexus and removes the muscles causing compression.

In some cases, 1st rib can also be removed. Infraclavicular approach in which an incision is made under the collar bone. This procedure is used to treat compressed veins.

In venous or arterial thoracic outlet syndrome, surgeon may deliver medications to dissolve blood clots.   

6 Prevention

There is no exact method to prevent thoracic outlet syndrome.

If thoracic outlet syndrome is untreated for years, it can cause permanent damage to the nervous tissue.

If a person belongs to the risk groups of thoracic outlet syndrome, avoid repetitive movements and lifting heavy object.

If a person is obese, losing weight will reduce the signs and symptoms.

Even if the person is not diagnosed with thoracic outlet syndrome or is not susceptible to the disease, he or she must avoid to carry heavy bags.

7 Lifestyle and Coping

Lifestyle modifications are necessary in order to cope with thoracic outlet syndrome.

Symptoms associated with thoracic outlet syndrome can be caused by a number of other condition which makes it difficult for diagnosis.

Many people experience thoracic outlet symptoms years before they are actually diagnosed which can cause stress and frustration.

Concerns must be discussed with doctors if symptoms persist and diagnosis hasn’t been confirmed.

Doctors or physical therapists will instruct some exercises at home to strengthen the muscles and joints surrounding thoracic cage.

In addition, some of the following things are recommended:

  • Maintaining good posture,
  • taking frequent breaks at work to move and stretch,
  • maintaining proper body weight,
  • applying heat or massaging the painful area,
  • avoid carrying heavy bags over shoulder,
  • avoid activities that may worsen the symptoms
  • and having good postures at work place. 

8 Risks and Complications

Some of the following factors can increase the risk of having thoracic outlet syndrome:

Repetitive motion

Doing same action again and again can cause thoracic outlet syndrome. Some sports which require repeated actions are

  • tennis,
  • golf,
  • baseball
  • and basketball.

Some occupations also require repetitive motions.


During pregnancy joint loosen up and lead to this disease.


Increases weight can put pressure on joints leading to compression. If treatment was not given in the early stages, progressive nerve damage can occur leading to requirement of surgery.

Surgery has higher risks than other treatment methods and may not treat the conditions always.  

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