TOS can be subdivided into three separate conditions caused by compression of a group of nerves or artery:

  • Arterial TOS  (compression of the axillary-subclavian artery)
  • Neurogenic TOS (compression of the brachial plexus nerves)
  • Venous TOS  (compression of the axillary-subclavian vein)

All three of these conditions are related to neurovascular compression within the thoracic outlet, but each type of TOS gives rise to a distinct clinical presentation. Use of this simple classification also aids in the understanding of the different clinical approaches to be taken in optimal diagnosis, testing, and treatment.

Other terms have sometimes been used to refer to subtypes of neurogenic TOS:

  • “traumatic TOS”
  • “true TOS”
  • “disputed TOS”
  • “nonspecific TOS”

Because these terms do not accurately reflect current understanding of neurogenic TOS, they have been largely discarded by many physicians who specialize in TOS.

Treatment for TOS may include either non-surgical management or surgery. Optimal treatment for all three forms of TOS requires the experience and expertise of health care professionals knowledgeable about these conditions, and a great deal of patience. The Washington University Center for Thoracic Outlet Syndrome at Barnes-Jewish Hospital draws upon a multidisciplinary team of specialists who are among the leaders in the care and treatment of TOS.