Thoracic outlet syndrome, or TOS, is a pain syndrome of the neck, chest and upper extremities. Specifically, the brachial plexus, a large network of nerves, leaves the neck and passes to the arm on each side. At the same time, large arteries and veins join the brachial plexus. After they meet, the nerves, arteries, and veins pass together through a series of tunnels to reach the arm. When these tunnels become narrowed, they can compress or stretch the nerves, arteries and veins. As a result, patients with TOS can suffer pain, weakness, abnormal sensations, or blood clots.

While thoracic outlet syndrome was first described 200 years ago, we have come to understand it more fully over the past few decades. We would like to help you understand TOS. We designed the NeoVista® website to help teach the history, causes and anatomy, and different types of thoracic outlet syndrome to patients and doctors.