Brachial Plexus Anatomy
There are three possible sites of compression in patients with thoracic outlet syndrome:
- The subclavian artery and lower roots of the brachial plexus may be compressed as they exit from the thoracic cavity, rise up over the first rib, and pass between the anterior and middle scalene muscles.
- The subclavian artery and vein and/or the lower trunk of the brachial plexus may be compressed beneath the clavicle in the costoclavicular space.
- The axillary artery and/or vein and/or one of the cords of the brachial plexus may be compressed in the sub-coracoid tunnel.