Thoracic outlet syndrome: a review for the primary care provider

Overview

This review, published in the Journal of Osteopathic Medicine in 2022 by Cavanna and colleagues, summarises what is known about thoracic outlet syndrome (TOS), a group of conditions in which the nerves and vessels between the neck and the arm are compressed. Its symptoms are common and often mistaken for other diagnoses. The authors searched PubMed following PRISMA methods and used 187 articles to address causes, examination findings and treatment.

Types and causes

Compression may occur in the scalene triangle, the costoclavicular space or the pectoralis minor space. Causes are congenital (such as a cervical rib), traumatic (whiplash, road accidents) or functional (repetitive arm activity). Three forms are recognised: neurogenic (about 95% of surgical cases), venous (about 3%) and arterial (about 1%). Neurogenic TOS is more common in women and venous TOS in men.

Diagnosis

Typical symptoms are pain and paraesthesia in the neck, shoulder, arm and hand, sometimes with occipital headache. Diagnosis is clinical. The upper limb tension test is the best initial screen because a negative result argues against brachial plexus compression, and a positive result should be followed by the elevated arm stress test. Adson's test alone has low specificity. Radiographs, ultrasound, MRI, CT or MR angiography and electromyography can help to separate neurogenic from vascular forms and to exclude other causes.

Management

Initial treatment of neurogenic TOS is conservative: physical therapy with stretching, posture correction and nerve glides, osteopathic manipulative treatment, injections and medication. The evidence is limited, mostly retrospective observations and case reports, and no randomised trials were found, so no single approach can be called best. Surgery is reserved for cases that do not respond. Venous and arterial forms need urgent assessment because of the risk of limb ischaemia and are treated with anticoagulation, thrombolysis and surgical decompression.