Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 20-45: Thoracic Outlet Syndromes + Key Features Download Section PDF Listen +++ +++ Essentials of Diagnosis ++ Compression of neurovascular structures supplying upper extremity +++ General Considerations ++ Intermittent or continuous pressure on elements of the brachial plexus and the subclavian or axillary vessels by anatomic structures of the shoulder girdle region results in symptoms and signs The neurovascular bundle can be compressed between the anterior or middle scalene muscles and a normal first thoracic rib or a cervical rib Predisposing factors Scarred scalene neck muscle secondary to neck trauma Sagging of the shoulder girdle, resulting from aging, obesity, or pendulous breasts Faulty posture Occupation Thoracic muscle hypertrophy from physical activity (eg, weight-lifting, baseball pitching) Predominant symptoms depend on whether obstruction affects neural or vascular structures + Clinical Findings Download Section PDF Listen +++ +++ Symptoms and Signs ++ Onset usually gradual but can be sudden Pain Numbness Weakness Swelling Vascular symptoms consist of arterial ischemia, characterized by Pallor of fingers on elevation of extremity Sensitivity to cold Gangrene of digits (rare) Venous obstruction marked by edema, cyanosis, and engorgement (also rare) +++ Differential Diagnosis ++ Osteoarthritis of cervical spine Tumors of the superior pulmonary sulcus, cervical spinal cord, or nerve roots Periarthritis of the shoulder + Diagnosis Download Section PDF Listen +++ +++ Imaging Studies ++ Chest radiography identifies presence of cervical rib MRI with arms held in different positions useful in identifying sites of impaired blood flow Angiography confirms intra-arterial or venous obstruction +++ Diagnostic Procedures ++ Reflexes not usually altered Symptoms can be provoked within 60 seconds over 90% of the time by having a patient elevate the arms in a "stick-em-up" position (ie, abducted 90 degrees in external rotation) Obliteration of the radial pulse with certain maneuvers of the arm or neck, once considered a highly sensitive sign of thoracic outlet obstruction, does not occur in most cases + Treatment Download Section PDF Listen +++ +++ Surgery ++ Required by < 5% of patients More likely to relieve neurologic rather than vascular component that causes symptoms +++ Therapeutic Procedures ++ Conservative measures (eg, physical therapy) to relieve compression of neurovascular bundle + Outcome Download Section PDF Listen +++ +++ Complications ++ Gangrene of the digits or venous obstruction if there is vascular obstruction +++ Prognosis ++ Greater than 95% of patients can be treated successfully with conservative therapy, consisting of physical therapy and avoiding postures or activities that compress the neurovascular bundle +++ Prevention ++ Avoid faulty posture or physical activities (eg, weight-lifting, baseball pitching) that compress neurovascular bundle +++ When to Refer ++ Persistent symptoms despite conservative therapy + References Download Section PDF Listen +++ + +Jones MR et al. Thoracic outlet syndrome: a comprehensive review of pathophysiology, diagnosis, and treatment. Pain Ther. 2019 Jun;8(1):5–18. [PubMed: 31037504] + +Yin ZG et al. Outcomes of surgical management of neurogenic thoracic outlet syndrome: a systematic review and Bayesian perspective. J Hand Surg Am. 2019 May;44(5):416.e1––17. [PubMed: 30122304]