The Superior Thoracic Aperture

Abstract

Thoracic outlet syndrome (TOS) is a condition related with neurovascular compression at the structures passing from the thoracic outlet to the axilla. The exact pathophysiology is still not clear because there is no definitive diagnostic tool and the patient report wide range of different symptoms. It is mainly divided into two categories: neurogenic and vascular TOS. Neurogenic TOS (nTOS) is much more common, mostly lower trunk of brachial plexus is effected. In vascular TOS (vTOS), mostly subclavian artery or vein is compressed. Anatomical variations in the thoracic outlet could also predispose patient to TOS. Duplex imaging is the preferred diagnostic tool for vTOS. For nTOS, electrophysiological tests or anterior scalene muscle blocks guide clinicians for deciding which patient would benefit from first rib resection. For first rib resection, transaxillary approach provides the greatest field view. Improved diagnostic modalities and better therapeutic strategies are needed. This chapter will cover the anatomy of thoracic outlet, clinical presentation and etiology of TOS, diagnositic modalities and treatment strategies for TOS.