Thoracic outlet syndrome

Thoracic outlet syndrome occurs when blood vessels and nerves near the collarbone become compressed. It often affects both sides of the body, but may be worse on one side.

Risk factors

Often, no specific cause for thoracic outlet syndrome can be found. You may be at risk if you have:

• drooping shoulders
• a past injury in this area
• an extra cervical rib (above the first rib)
• muscle enlargement (from exercise or work)

Symptoms

Symptoms may range from mild to severe, and may include:

• pain in the neck, shoulder and arm
• numbness or discomfort in the last three fingers and inner forearm
• weakness in hand muscles
• swelling in the arm
• a bluish color to the arm and hand