Four cases of thoracic outlet syndrome are described, with observations to support a primary myofascial etiology involving the scalene and smaller pectoral muscles. It is believed that thermography can be extremely helpful as an aid in diagnosis of thoracic outlet syndrome and, when combined with Doppler blood flow studies and photoplethysmography, can help localize the site of the pathosis. Thermography is a sensitive, non-invasive test that most clearly demonstrates pathology in the hand views. Global changes throughout the entire hand suggest vascular or reflex autonomic involvement, while a more dermatomal distribution suggests specific neurologic involvement. Vigorous stretching and a unique form of myofascial release manipulation has been successful in rapidly treating patients with thoracic outlet syndrome. Follow-up thermography (perhaps hand and forearm views only) can be used to monitor response to treatment and to objectively document improvement.