Introduction to Thoracic Outlet Syndrome

Risk Factors for Thoracic Outlet Syndrome

A risk factor is anything that increases a person's changes of getting a disease or condition such as thoracic outlet syndrome (TOS). Risk factors for TOS include:

• Occupation - Epidemiologic studies have shown that thoracic outlet syndrome is associated with certain occupations that involve positioning the arm in such a way that can cause compression of the space between the neck and shoulder. The result is compromised blood flow to the subclavian blood vessels nourishing the arm, and/or compression of the brachial plexus causing significant pain. Examples of these occupations include:

  • heavy lifting
  • working in a static position for an extended period of time
  • prolonged raising of the arm above the head (e.g. housepainters)
  • secretaries
  • computer operators
  • benchworkers
  • jackhammer operators
  • electricians
  • carpenters
  • violinists
  • flutists
  • assembly line work

Certain daily activities seem to be associated with thoracic outlet syndrome including holding the phone between the shoulder and neck which may cause compression in the shoulder region and result in numbness or pain.

• Trauma

  • fracture of the clavicle
  • trauma to the shoulder
  • hyperextension injuries of the neck (whiplash injuries)
  • jerking injury to the neck/shoulder area which results in chronic muscle spasm

• Congenital anomalies

Congenital anomalies (cervical rib and band syndrome) are abnormal fibromuscular bands present at birth that irritate or compress the brachial plexus. This can lead to the development of TOS.

• Postural distortions such as drooping or sagging shoulders