| Abstract: | Thoracic Outlet Syndromes (TOS) consists of a group of distinct pathologies arising from compression or impingement of structures at the thoracic outlet. The structures at risk are, from anterior to posterior, subclavian vein (venous — VTOS), subclavian artery (arterial — ATOS) and brachial plexus (neurogenic — NTOS). NTOS is the most common presentation, usually caused by compression of the brachial plexus at the scalene triangle or pectoralis minor space. Neurogenic compression syndromes at the carpal and cubital tunnels should be excluded. Management of NTOS is usually conservative, employing physiotherapy and postural exercises, but pain or muscle wasting may be indications for surgery. VTOS is caused by compression of the subclavian vein at the costoclavicular junction, resulting in venous thrombosis (Paget—Schroetter syndrome) often as a result of exercise in fit young muscular people or musicians. Positional swelling of the upper limb without thrombosis is termed McCleery's syndrome. In acute thrombosis, clot lysis, first rib excision and venoplasty may be indicated. ATOS occurs due to compression of the subclavian artery at the scalene triangle, often in association with an anomalous bony structure, such as cervical rib, causing post-stenotic aneurysmal dilation of the artery, thrombosis and distal embolization. Acute upper limb ischaemia necessitates urgent cervical rib excision and arterial reconstruction. |
