Thoracic Outlet Syndrome
Thoracic Outlet Syndrome (TOS) is used to describe upper extremity symptoms and according to recent reports 1,2 is defined as compression of the neurovascular structures in the interscalene tri-angle, as it exits the thoracic girdle. The bony anatomy of thoracic outlet, which will be discussed in further detail, can be defined by the space between the first thoracic vertebra, first rib, and manubrium of the sternum.1 Thoracic Outlet Syndrome is not specific in determining the struc-ture being compressed. The clinical signs are variable due to the variety of tissue and entrapment locations, thus leading to its categorization as vascular or neurogenic. Vascular being defined as arterial and venous, while neurogenic is defined as either true or