Thoracic outlet syndrome (TOS) is a spectrum of disorders resulting from the compression of the neurovascular structures within the thoracic outlet. The three main subtypes of TOS are defined by the anatomic structure affected by the extrinsic compression. In the most common subtype--neurogenic TOS--the brachial plexus is compressed and symptoms include pain, arm paresthesias, and sometimes weakness. Venous TOS is characterized by the compression of the subclavian vein and its resultant thrombosis. Arterial TOS is the least common and is distinguished by the compression of the subclavian artery and the development of aneurysms or stenoses with distal embolization. Treatment options include physical therapy and surgical first rib resection via the transaxillary or supraclavicular approach. The diagnosis of TOS and appropriate patient selection for intervention are challenging due to the frequent presence of vague symptoms in neurogenic TOS. Due to the relative rarity of this condition, different approaches to diagnosis and management exist, and optimum management strategies continue to evolve.

The primary goals of this Special Issue on the "Diagnosis and Treatment of Thoracic Outlet Syndrome" are to describe new and established diagnostic and treatment modalities for TOS; to discuss approaches to complex clinical situations, such as reoperative treatment; and to review new research developments in the field of TOS.