Thoracic Outlet Syndromes

Abstract

The term thoracic outlet syndrome is used to describe a variety of disorders caused by abnormal compression of neural, arterial, and rarely venous structures at the base of the neck or in the thoracic outlet. Many mechanisms for this compression have been described. These include cervical ribs, anomalous ligaments in the position of the rib, hypertrophy of the scalenus anterior muscle, and positional changes that alter the normal relationship of the first rib to the structures that cross over it. The confusing assortment of names used to describe the syndrome has been related to the assumed mechanisms of symptom production, namely cervical rib, scalenus anticus syndrome, costoclavicular syndrome, and hyperabduction syndrome.