Thoracic Outlet Syndrome

Thoracic outlet syndrome (TOS) occurs when nerves or blood vessels become compressed in the space between the collarbone and the first rib, known as the thoracic outlet. This area contains important structures that travel from the neck into the shoulder, arm, and hand.

When compression occurs, it can lead to symptoms such as arm pain, numbness, tingling, weakness, or heaviness in the arm or hand. Many people also experience discomfort in the neck or shoulder region.

Thoracic outlet syndrome can sometimes be mistaken for other conditions such as pinched nerves in the neck or cervical disc problems, because the symptoms may feel very similar.

Fortunately, many cases of thoracic outlet syndrome respond well to conservative care focused on improving posture, restoring proper movement, and reducing compression in the neck and shoulder region.

Symptoms of Thoracic Outlet Syndrome

Thoracic outlet syndrome can produce a variety of symptoms depending on whether nerves or blood vessels are affected.

Common symptoms include:

• Pain in the neck, shoulder, or arm
• Numbness or tingling in the arm, hand, or fingers
• Weakness in the arm or hand
• Heaviness or fatigue in the arm during activity
• Tingling that worsens when the arms are raised
• Coldness or color changes in the hand or fingers (in vascular cases)

Symptoms often worsen with activities such as lifting the arms overhead, carrying heavy objects, or prolonged shoulder positioning.

What Causes Thoracic Outlet Syndrome?

Several factors may contribute to compression within the thoracic outlet.

Common causes include:

• Poor posture or forward head posture
• Rounded shoulders or slouched sitting
• Tight neck and chest muscles
• Repetitive overhead activities
• Previous neck or shoulder injuries
• Anatomical variations such as a cervical rib
• Muscle imbalances in the neck and shoulder region
• Occupations involving repetitive arm movement

Poor posture is one of the most common contributing factors. When the head and shoulders move forward, it can reduce the space in the thoracic outlet and increase pressure on nerves and blood vessels.

Thoracic Outlet Syndrome vs Pinched Nerve

Symptoms of thoracic outlet syndrome are often similar to those of a pinched nerve in the neck (cervical radiculopathy).

Both conditions can cause:

• arm pain
• numbness or tingling in the hand
• weakness in the arm

However, the underlying cause may be different. In thoracic outlet syndrome, compression typically occurs near the collarbone or shoulder region, whereas a pinched nerve originates from the cervical spine.

You can learn more about this condition on our Pinched Nerve in the Neck page.

The Role of Posture

Posture plays a major role in thoracic outlet syndrome.

Forward head posture and rounded shoulders can reduce the space between the collarbone and first rib. Over time, this can place additional pressure on the nerves and blood vessels traveling into the arm.

Improving posture and restoring proper muscle balance may help reduce compression in the thoracic outlet region.

You can learn more on our Forward Head Posture and Posture Correction pages.

Thoracic Outlet Syndrome Treatment in Newmarket

At Chiropractic on Eagle, the first step in managing thoracic outlet syndrome is identifying the factors contributing to nerve or vascular compression.

Every patient receives a comprehensive evaluation which may include:

• posture analysis
• orthopedic and neurological testing
• spinal movement assessment
• muscle and joint evaluation
• digital X-rays if clinically necessary

This allows us to determine whether symptoms are related to postural stress, muscle imbalance, spinal dysfunction, or nerve irritation.

Treatment may include:

• gentle chiropractic spinal adjustments
• soft tissue therapy for tight muscles
• posture correction strategies
• stretching, traction and rehabilitation exercises
• ergonomic and lifestyle recommendations

The goal is to reduce compression within the thoracic outlet and restore normal movement of the neck, shoulders, and upper spine.

Thoracic Outlet Syndrome Chiropractor in Newmarket

For more than 23 years, Chiropractic on Eagle has helped patients in Newmarket, Aurora, East Gwillimbury, Bradford, and surrounding York Region communities with spinal and nerve-related conditions affecting the neck, shoulders, and arms.

If you are experiencing arm pain, numbness, tingling, or weakness, we would be happy to help determine whether thoracic outlet syndrome or another condition may be contributing to your symptoms.

If you are experiencing symptoms of thoracic outlet syndrome, we would be happy to help determine whether chiropractic care may be appropriate for your condition.

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