Thoracic Outlet Syndrome | White Plains Hospital

Thoracic Outlet Syndrome

Thoracic Outlet Syndrome (TOS) is a relatively uncommon condition caused by compression of either nerves or blood vessels that supply the arms and hands. Nerves to your arms and hands originate in the neck and traveled your arms by passing through an area of the body referred to as the thoracic outlet. This is a narrow, triangular shaped region that is bounded on the bottom by a rib (1st rib) and on each side by muscles (Scalene muscles). Within this narrow triangular space, the nerves and blood vessels to your arms travel as well as other tissues.


  • Enlargement of muscles of triangle as can be seen in weight lifters, athletes, or individuals who work with their arms over their heads such as mechanics or painters
  • Trauma to the shoulder, anterior chest wall or collarbone
  • Extra congenital rib above the 1st rib
  • Abnormal fibrous band or ligament from the spine to the ribs
  • Tumors

Risk Factors

  • Repetitive motions with the arms extended over the head
  • Extensive muscularity of neck and shoulders
  • Poor posture with shoulders drooping forward


  • Nerve symptoms most common (nerve sits onto of rib in direct contact)
    • Pain in neck, shoulder, arm or hand
    • Numbness in arm or fingers (especially 4th and 5th finger) worse when using arms over head
    • Weakness in muscles of arms, hands, or shoulders
    • Fatigue in arms or hands
  • Vascular symptoms although less common can be more serious
    • Hands or arms can turn blue or pale, especially when the arms or elevated or lifted over head
    • Hands or arms feel cold or painful at all times

Diagnostic Tests

  • Difficult to make, frequently made on clinical basis
  • X-ray to look for abnormal or extra rib
  • Blood flow evaluation of arms to look for compression of arteries or veins
  • Magnetic Resonance Imaging (MRI) to look for abnormal fibrous bands or ligaments or tumor
  • Nerve Conduction Studies to look for evidence of nerve damage around should and thoracic outlet
  • CT Angiogram to evaluate possible vascular compression or occlusion


  • Usually conservative unless evidence of significantly impaired blood flow to arm
  • Physical therapy with exercises designed to open the space of the triangle and strengthen the shoulder muscles
  • Exercises to promote better posture and take pressure off the triangle
  • Physical manipulation by chiropractors or physical therapist to widen the space
  • Avoidance of activities which require patient to elevate their arms over their heads for long periods
  • Weight loss if obese
  • Avoidance of sleeping with arms over head
  • Surgery
    • If symptoms are severe, or there is evidence of vascular compromise with impairment of blood flow to the arm, surgery may be recommended
    • Surgery can alleviate the pressure on the blood vessels or nerves
    • Usually performed through either a small incision in the armpit or an incision just above the collarbone
    • Removal of the 1st rib and any constricting bands or ligaments and release of the muscular attachments will open the triangular space
    • Occasionally bypass graft or angioplasty will be required to repair blood vessel damage caused by chronic compression

Here at White Plains hospital, a skilled team of Thoracic Surgeons with over 3 decades of experience in treating this condition can advise you as to the type of conservative measures to treat your symptoms and also discuss surgical options if they are deemed appropriate.