Cervical rib causing thoracic outlet syndrome

Thoracic outlet syndromes are due to compression of any of the structures (brachial plexus, subclavian artery, subclavian vein) that traverse the confined space between the clavicle and first rib. Anatomic abnormaliaties such as a cervical rib (shown), musculotendinous abnormalities or scarring can contribute to the pathology.