The Thoracic Outlet Syndrome Is Underrated

Abstract

The thoracic outlet syndromes (TOS) are caused by congenital or developmental anatomic anomalies of musculoskeletal tissues that cause abnormal compression and irritation of the brachial plexus and subclavian vessels. The most obvious anomaly is a cervical rib, but this is found in only about 10% of patients with TOS. The other 90% who develop severe neuromuscular symptoms affecting the neck, shoulder, and upper extremity are found to have soft-tissue anomalies usually related to the middle and anterior scalene muscles. Although these anomalies have been carefully classified and reported, 1,2 only the surgical team can appreciate the remarkable anatomic variations that cause the severe neurovascular symptoms. Extensive (and expensive), sophisticated neuroelectric studies, magnetic resonance imaging scans, computed tomography scans, and vascular laboratory studies completely fail to demonstrate the anatomic variations of the soft tissues and the neurologic compression-irritation mechanisms that are the basic cause of the symptoms. 3,4 Thus, the physician