Thoracic outlet syndrome: a narrative review.

The Thoracic Outlet Syndrome (TOS) results from compression of the brachial plexus, the subclavian artery and the subclavian vein in the thoracic outlet region. This compression may take place between the clavicle and the first rib or by a number of anatomical variations. Neurological compression is the most common form of thoracic outlet syndrome. Vascular complications occur infrequently. Arterial complications usually result from compression of the subclavian artery by a complete cervical rib. Venous complications are often related to muscle compression of the subclavian vein. The neurogenic form, previously described, is the most common, constituting more than 95% of cases, while the venous represents 2% to 3%, and the arterial, about 1%. Risk factors include biotype and individual variations such as genetics, age and gender. In Brazil, there are no data on the epidemiology of TOS. Given the suspicion of TOS, a detailed clinical evaluation is necessary, followed by complementary exams to elucidate the cause. The treatment is directed according to the etiology and the presence or absence of complications. The purpose of this study was to perform a narrative review on TOS, focusing on its etiology, pathophysiology, epidemiology, clinical evaluation, complementary exams, differential diagnoses, and treatment.