Anterior Scalene Anomaly in a Patient With Arterial and Neurogenic Thoracic Outlet Syndrome.

Compression of the neurovascular structures of the upper extremity as they pass through the thoracic outlet result in thoracic outlet syndrome. The myriad of symptoms associated with the syndrome vary based on the structure(s) compressed: the subclavian artery/vein or the inferior trunk of the brachial plexus. This is a common site of compression especially in the presence of upper extremity injury, overuse or anatomical abnormalities. Majority of patients present with neurogenic pain and weakness; herein, we present the case of a patient with symptoms of both arterial and neurogenic compression caused by aberrant anterior scalene anatomy. These patients are excellent surgical candidates for first rib resection and anterior scalenectomy. A transaxillary approach offers the clinician an adequate window to identify anatomical abnormalities intraoperatively and safely excise the first rib and anterior scalene muscle.