Thoracic outlet syndrome (TOS) is a condition where the nerves or arteries that go to the arm and hand get squeezed between soft tissues near the side of the neck. With few exceptions, surgery is a last resort for treating TOS. Most people are able to get a handle on their TOS symptoms through a therapy program. Specialized exercises can improve muscle balance and posture to lessen your TOS symptoms. A physical or occupational therapist usually designs the exercise program. The therapist can also suggest ways to do your work with greater ease and fewer TOS symptoms. Work postures and tasks can contribute to symptoms of TOS.