Thoracic Outlet Syndrome Vascular Case Conference WVU Dept. of Surgery Mary Carolyn C. Vinson, DO PGY-1 Definition • Thoracic outlet syndrome is a disease of extrinsic compression of the neurovascular structures thoracic outlet Anatomy of Thoracic Outlet QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture. More Anatomy http://intraspec.ca/images/brachialplexus.jpg Pathophysiology • Brachial plexus trunk & subclavian vessels are subject to compression or irritation • Three narrow passageways @ base of neck toward the axilla & proximal arm. – Interscalene Triangle – Costoclavicular Triangle – Subcoracoid Space • Repetitive trauma to especially – Lower trunk – C8-T1 spinal nerves Interscalene Triangle • Triangle borders – Anteriorly: anterior scalene muscle – Posteriorly: middle scalene muscle – Inferiorly: medial surface of the first rib • Area small at rest & becomes even smaller with certain movements • Fibrous bands, cervical ribs, and anomalous muscles, may further constrict this triangle Costoclavicular Triangle • Borders – Anteriorly by middle 3rd of clavicle – Posteromedially by 1st rib – Posterolaterally by upper border of scapula Subcoracoid Space • Is beneath the coracoid process just deep to the pectoralis minor tendon QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture. QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture. Etiology • Anatomic Factors – Interscalene compression – Costoclavicular compression – Subcoracoid compression Congenital • • • • • • • • • • • Cervical rib Rudimentary first rib Scalene muscle abnormalities Fibrous bands Bifid clavicle First rib exostosis Enlarged C7 transverse process Omohyoid muscle abnormalities Anomalous transverse cervical artery Postfixed brachial plexus Flat clavicle Traumatic Factors • • • • Fractured clavicle Humeral head dislocation Upper thorax crush injury Sudden effort of shoulder girdle muscles • C-spine injuries/cervical spondylosis Clinical Presentation • Depends on which anatomic structure is compressed in the area of the thoracic outlet – Axillary-subclavian artery – Vein • Paget-Schroetter syndrome, or effort thrombosis – Neurogenic • brachial plexus, or sympathetic nerves • Clinical syndrome results from any mixture or an isolated compression of structures Neurologic Presentation • More common • Strenuous physical exercise precipitates • Pain & paresthesias 95% of patients – Neck, shoulder, arm & hand – Positional: arm abduction & neck hyperextension • True motor weakness w/ atrophy – Usually Ulnar nerve distribution : • hypothenar/interosseus muscles in 10% – medial arm & hand – 4th & 5th fingers • Sensory fibers on outside of nerve bundles 1st affected Arterial Presentation • Signs: – Distal embolization – Post-stenotic dilation or aneurysm of subclavian a. – True arterial occlusion • Symptoms: – Pain usually diffuse & assoc. w/ coldness, weakness, easy fatigability of hand & arm • Unilateral Raynaud's phenomenon – 7.5% patients – precipitated by hyperabduction or carrying heavy objects Venous Presentation • Venous obstruction less common – Effort thrombosis – Paget-Schroetter syndrome • Signs & Symptoms – Edema – Discolored – Aches Differential Diagnosis • Neurologic,vascular, pulmonary, cardiac, and esophageal disorders. • More common Differential Diagnosis include – herniated cervical disk – cervical spondylosis – peripheral neuropathies Clinical Diagnosis • Positive findings for all tests: – ⇓ or loss of the radial pulse – reproduction of symptoms • Adson/Scalene test: – Deep Breath, fully extends neck, and turns head to the side • Costoclavicular test: – shoulders drawn inferiorly and posteriorly • Hyperabduction test: – arm is hyperabducted to 180 degrees Imaging • CXR & C-spine films: – detect cervical ribs & degenerative changes • Cervical CT performed if: – osteophytic changes & intervertebral space narrowing present • Angiography indicated for: – Pulsating paraclavicular mass – Absent radial pulse – Paraclavicular bruit Ulnar Nerve Conduction Velocity • Points of stimulation include: – – – – Supraclavicular fossa Middle upper arm Below elbow Wrist • Normal value across thoracic outlet: 72 m/sec • Any value < 70 m/sec indicates compression Angiogram Shows compression of subclavian artery at two levels: proximally between clavicle and cervical rib (long arrow) and distally by subclavius muscle (short arrow). Venogram: R subclavian vein Venogram Complete occlusion of Left subclavian vein (arrow) where it crosses the first rib Treatment • Physical therapy is initial treatment • Many patients get relief from non-operative therapy – esp. for neurogenic TOS • Simple changes in posture may result in opening the thoracic outlet – PT= Strengthen muscles supporting improved posture Surgical Treatment for TOS • Reserved for patients w/ symptoms persisting after aggressive physical therapy • Equals about 5% of PTs w/ TOS require surgery • “There are multiple compressive forces, the first rib is the common denominator, and extirpation of this structure is the “gold” standard for therapy.” • Urschel et al. 2003 Surgical Outcomes • > 2200 patients showed excellent or good results after operation in over 90% of cases • Urschel et. al 1997 • Symptoms recur in approx 10% • Less than 2% require re-operation Surgical Pictures 1st thoracic rib removed to decompress neurovascular structures of TOS Recurrent Thoracic Outlet Syndrome • Approx 1-2% of PTs have persistent or worsening symptoms after operation – Most have recurrence within 3 months • History, physical examination, and nerve conduction studies should preformed Types of Recurrence • Pseudorecurrence – Cervical rib or the second rib was resected instead of the first rib – First rib was resected instead of the causative cervical rib • True recurrence – First rib was incompletely resected – Excessive scar development around the brachial plexus Re-operation for Failed Initial Operation on TOS • 80% of patients after re-operation = improvement in symptoms • 7% required a second re-operation Summary • • • • • • TOS mimics many other processes Compression is the causative agent 1st rib is often the culprit History ⇒ PE ⇒ UNVC XR ⇒ CT ⇒ Angio/Venogram Physical therapy ⇒ Surgery • Note: DVT and Arterial Occlusions are treated with Anticoagulation/Thrombectomy References • Thomas S. Maxey, MD, T. Brett Reece, MD, Peter I. Ellman, MD, Curtis G. Tribble, MD, Nancy Harthun, MD, Irving L. Kron, MD, John A. Kern, MD. Safety and efficacy of the supraclavicular approach to thoracic outlet decompression.Ann Thorac Surg 2003;76:396400 • Harold C. Urschel, Jr, MD,, Amit N. Patel, MD. Surgery Remains the Most Effective Treatment for Paget-Schroetter Syndrome: 50 Years' Experience. Ann Thorac Surg 2008;86:254-260. • Urschel HC Jr and Razzuk MA. Upper plexus thoracic outlet syndrome: optimal therapy. . Annals of Thoracic Surgery 1997 63(4):935-9. • Harold C. Urschel Jr and Amit Patel. Thoracic outlet syndromes. Current Treatment Options in Cardiovascular Medicine. Vol 5, No 2. April 2003. 1092-8464 • Urschel HC Jr, Razzuk MA.The failed operation for thoracic outlet Syndrome: the difficulty of diagnosis and management.Ann Thorac Surg. 1986 Nov;42(5):523-8 • • • http://brighamrad.harvard.edu/Cases/bwh/hcache/170/full.html http://www.ajronline.org/cgi/content-nw/full/183/1/113/FIG9 http://www.ctsnet.org/doc/7628