Thoracic Outlet Syndrome

What is Thoracic Outlet Syndrome?

Thoracic Outlet Syndrome (TOS) is a group of conditions where the nerves, arteries and/or veins in the “thoracic outlet”, or the path from your lower neck to your arm pit are compressed.

Nerve compression is the most common and presents with pain, weakness, and occasionally loss of muscle at the base of the thumb. The venous type results in swelling, pain, and possibly a bluish coloration of the arm. The arterial type results in pain, coldness, and paleness of the arm. One, two or all of these compressions can occur at once.

TOS usually affects otherwise healthy, young and active people and is much more commonly caused by injury, overuse of arms, or a trauma, rather than disease.

Thoracic Outlet Syndrome is treatable and usually has no long term effects.

What causes Thoracic Outlet Syndrome?

Thoracic Outlet Syndrome can be caused by:

• Compression of nerves
• Compression of the subclavian artery or subclavian vein on the side of the throat or upper chest
• Injury to the artery due to an abnormality in a neck rib or other bony irritation
• Injury or compression of the vein. This could lead to a progressive narrowing of the vessel and eventual clot formation
• Trauma
• Repetitive arm movements
• The presence of a cervical rib or other congenital abnormality
• Tumour
• Pregnancy

The condition affects about 1% of the population. It is more common in women than men and it occurs most commonly between 20 and 50 years of age.

What are the signs/symptoms of Thoracic Outlet Syndrome?

TOS affects mainly the upper limbs, with signs and symptoms manifesting in the shoulders, neck, arms and hands.

There are signs and symptoms that can occur for all three types of Thoracic Outlet Syndrome (nerve, venous, arterial), such as:

• Numbness or tingling that can be sudden or gradual, usually in your arm and hand.
• A stabbing, burning or aching pain in the arm that can be sudden or gradual, constant or intermittent.
• Worsening pain when lifting the affected arm or when moving it repetitively.
• An easily fatigued arm, weakness.

Specifically, due to constriction of blood flow into the arm, venous and arterial TOS can show signs such as:

• One hand colder than the other hand.
• A blue discolouration of the skin on the arm.
• Swelling in the arms and hands.
• Arm paleness.
• Vision disturbances, eye problems (very rare)

Continued constriction can lead to:

• Sores on fingers that resist healing
• Gangrene

How will Thoracic Outlet Syndrome affect my health?

Thoracic Outlet Syndrome is treatable and usually has no long term effects. Once a TOS has been diagnosed and treated, it is advisable to not place repetitive stress on the affected limb, and to maintain a healthy lifestyle with physical exercise.

Left unassessed, the TOS can result in a DVT or blood clot that can adversely affect the arm, the thoracic outlet or another area in the body if the clot travels through the body.

I think I have Thoracic Outlet Syndrome – What should I do?

If you have any of the symptoms above:

Visit your GP: Your GP can provide you with a check-up and a referral to a Vascular Surgeon. Advise the doctor of any recent injury, trauma or accident you may have experienced, or if you have a repetitive or highly physical job or sport.

See a Vascular Surgeon: You will be asked questions about symptoms and medical history, including questions about family members. The vascular surgeon will also perform a physical exam.

The vascular surgeon will prescribe one or a combination of the following tests to help diagnose the condition:

• Stress maneuver testing—placing the arm or head in certain positions
• Computed tomography (CT) scan
• Magnetic resonance imagining (MRI)
• Catheter-based arteriography or venogram
• An anesthetic block injection can temporarily improve symptoms and aid diagnosis.

What treatment options does SVS offer for Thoracic Outlet Syndrome?

Sydney Vascular Surgery offers conservative, and surgical treatment options. During your visit, your surgeon will advise you on the best treatment option, or options, available to you. Your surgeon will also perform a general health check that will inform the treatment plan.

The best results come from a combination of medical treatment and physical therapy. SVS can provide your medical treatment and conservative management, and can advise your physiotherapist, chiropractor, osteopath or occupational therapist on your condition.

Conservative management

SVS provides expert advice for the ongoing management and healing of your TOS post treatment. For venous or arterial TOS, the surgeon may include advice on anticoagulation/platelet medications to prevent or treat blood clots.

Surgical treatments include:

First Rib Excision

This surgery involves the removal of the uppermost rib, closest to the head, just under the collarbone. It is called a cervical rib because it attaches to the cervical vertebrae. First rib excision can also include the removal of the anterior scalene muscle if this muscle is also compressing the nerves, veins or arteries.

Under general anesthetic, an incision is created either in the armpit, the back of the neck or near the collarbone. The rib is cut away from the cervical vertebrae and removed. Vein and arterial health and surrounding muscle condition is checked prior to the closure of the incision.

Arterial Bypass

If arterial compression is diagnosed, a surgery called thoracic outlet decompression is the next step. Depending on the damage to the artery, an arterial bypass may be part of this surgery.

The aim of this surgery is to bypass a damaged or compressed artery to return the blood flow to the arm back to normal, and to prevent or treat blood clots resulting from the compression.

Under general anesthetic, the subclavian artery is bypassed around any bones or muscles that are causing the compression, using a synthetic or natural graft. This bypass reroutes the blood around the compression. The compressed area is left unchanged.

Helpful Links:

Thoracic Outlet Syndrome (TOS) https://vascular.org/patient-resources/vascular-conditions/thoracic-outlet-syndrome