Thoracic outlet syndrome is a group of disorders caused by pressure or compression against the nerves or blood vessels in the space behind and below the collarbone (the thoracic outlet). Thoracic outlet syndrome is more common in women than men and usually starts between 20 and 50 years of age.
There are three main kinds of thoracic outlet syndrome. The classification depends on what is being compressed – a nerve, a vein or an artery.
- Neurogenic (neurological) thoracic outlet syndrome
- Vascular thoracic outlet syndrome
- Nonspecific type thoracic outlet syndrome
Ninety-five percent of thoracic outlet syndrome cases are due to compression of nerves to the arm.
What causes thoracic outlet syndrome?
Thoracic outlet syndrome can be caused by various things, such as:
- Pregnancy
- Poor posture
- Tumors that press on nerves
- An acute injury causing trauma such as whiplash or a fall
- A chronic injury, such as repetitive arm and shoulder movements
- An anatomical defect, such as an extra rib or an abnormal first rib
Symptoms of thoracic outlet syndrome
Thoracic outlet syndrome affecting a nerve will usually cause the following symptoms:
- Pins and needles sensation in the fingers or hand
- Numbness in the fingers and hand
- Cold hands
- Dull ache in the neck, shoulder, or armpit
- Change in hand color
- Weakening grip
Thoracic outlet syndrome affecting a vein will usually cause the following symptoms:
- Pale skin
- Weak or absent pulse in the affected arm
- Cool and pale skin on the affected arm
- Numbness or tingling in the arm
- Swelling of the arm or fingers
- Weakness in the neck or arm
Thoracic outlet syndrome affecting an artery will usually cause the following symptoms:
- A change in skin color
- Sensitivity to cold in the hands and fingers
- Swelling
- Poor blood circulation or pins and needles in the arms, hands and fingers
How is thoracic outlet syndrome diagnosed?
Diagnosing thoracic outlet syndrome can be difficult because the symptoms resemble those of many other disorders and injuries, such as rotator cuff injuries, fibromyalgia, multiple sclerosis, and cervical disc disorders. Your doctor will perform a physical exam and may also use the following tests to help rule out other conditions:
- Pulse volume recordings
- Chest and cervical spine X-rays
- Doppler ultrasound
- Nerve conduction studies
- Computed tomography (CT) scan of the chest and spine
- Magnetic resonance imaging (MRI) scan of the chest and spine
- Magnet resonance angiography (MRA)
- Venography or arteriography
- Electromyography (EMG)
- Blood tests
- Vascular studies of the veins and arteries
How is thoracic outlet syndrome treated?
Treatment for thoracic outlet syndrome will vary depending on the type that you have. If your nerves are affected, you’ll be initially treated with physical therapy and medications. Most patients improve after this, but you may need decompression surgery if these measures aren’t enough.
If thoracic outlet syndrome is affecting your veins, the clot will be treated with thrombolysis, blood thinners or angioplasty. In rare cases, the vein may need to be repaired with surgery.
If thoracic outlet syndrome is affecting your arteries, you’ll likely need surgery to repair the damaged artery with a graft.