How is thoracic outlet syndrome diagnosed?

Making a proper diagnosis is the most important step in TOS. Doctors who treat this condition include vascular surgeons, chest (thoracic) surgeons and vascular medicine physicians.

To diagnose your condition, your doctor will perform a complete physical exam and will review the results of previous diagnostic tests.

In some cases, a thorough evaluation by a skilled neurologist may be recommended to rule out cervical spine disease or other neurological conditions that may be mimicking or causing your symptoms.

Additional tests performed to diagnose thoracic outlet syndrome include:

  • 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 (neck) spine 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 (pressure), which can mimic neurogenic thoracic outlet syndrome
  • Magnetic resonance imaging with angiography (MRA) to view blood vessels
  • Arteriogram/venogram (X-ray that uses dye to look at blood flow)
  • Blood tests

Is thoracic outlet syndrome serious?

Although many cases of thoracic outlet syndrome (TOS) can’t be prevented, the condition is treatable. If left untreated, TOS can cause complications, such as:

  • Permanent arm swelling and pain (especially in patients with venous TOS)
  • Ischemic ulcer of the fingers (open sore caused by reduced blood flow)
  • Gangrene (the death of body tissue, often caused by a loss of blood flow)
  • Blood clot
  • Pulmonary embolism (obstruction in a blood vessel due to a blood clot)
  • Neurogenic complications, such as permanent nerve damage

Last reviewed by a Cleveland Clinic medical professional on 07/19/2019.

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy