what is tos

Thoracic Outlet Syndrome (TOS) is a group of conditions in which there's pressure on blood vessels or nerves in the area between the neck and the first rib. This narrow passageway is crowded with blood vessels, nerves, and muscles. TOS occurs when nerves or blood vessels are compressed by the rib, collarbone, or neck muscles at the top of the outlet. Symptoms of TOS vary depending on the type, but they can include pain, tingling, and numbness in the arms and hands, weakness and/or a "pins and needles" feeling when raising the hands, weakness in the fifth ("little") finger, and paleness in the palm of one or both hands when they're raised above the shoulders, with the fingers pointing to the ceiling. Common causes of TOS include trauma from a car accident, repetitive injuries from a job or sport, and pregnancy. Differences in anatomy, such as having an extra or irregular rib, also can cause TOS. Treatment often involves physical therapy and pain relief. Most people improve with these treatments. For some, surgery may be recommended.