Thoracic outlet syndrome: a review for the primary care provider
Authors: Cavanna Angela C. , Giovanis Athina , Daley Alton , Feminella Ryan , Chipman Ryan , Onyeukwu Valerie 
Published: August 2022

Abstract

Context
Thoracic outlet syndrome (TOS) symptoms are prevalent and often confused with other diagnoses. A PubMed search was undertaken to present a comprehensive article addressing the presentation and treatment for TOS.

Objectives
This article summarizes what is currently published about TOS, its etiologies, common objective findings, and nonsurgical treatment options.

Methods
The PubMed database was conducted for the range of May 2020 to September 2021 utilizing TOS-related Medical Subject Headings (MeSH) terms. A Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) systematic literature review was conducted to identify the most common etiologies, the most objective findings, and the most effective nonsurgical treatment options for TOS.

Results
The search identified 1,188 articles. The automated merge feature removed duplicate articles. The remaining 1,078 citations were manually reviewed, with articles published prior to 2010 removed (n=771). Of the remaining 307 articles, duplicate citations not removed by automated means were removed manually (n=3). The other exclusion criteria included: non-English language (n=21); no abstracts available (n=56); and case reports of TOS occurring from complications of fractures, medical or surgical procedures, novel surgical approaches, or abnormal anatomy (n=42). Articles over 5 years old pertaining to therapeutic intervention (mostly surgical) were removed (n=18). Articles pertaining specifically to osteopathic manipulative treatment (OMT) were sparse and all were utilized (n=6). A total of 167 articles remained. The authors added a total of 20 articles that fell outside of the search criteria, as they considered them to be historic in nature with regards to TOS (n=8), were related specifically to OMT (n=4), or were considered sentinel articles relating to specific therapeutic interventions (n=8). A total of 187 articles were utilized in the final preparation of this manuscript. A final search was conducted prior to submission for publication to check for updated articles. Symptoms of hemicranial and/or upper-extremity pain and paresthesias should lead a physician to evaluate for musculoskeletal etiologies that may be contributing to the compression of the brachial plexus. The best initial provocative test to screen for TOS is the upper limb tension test (ULTT) because a negative test suggests against brachial plexus compression. A positive ULTT should be followed up with an elevated arm stress test (EAST) to further support the diagnosis. If TOS is suspected, additional diagnostic testing such as ultrasound, electromyography (EMG), or magnetic resonance imaging/magnetic resonance angiography (MRI/MRA) might be utilized to further distinguish the vascular or neurological etiologies of the symptoms. Initial treatment for neurogenic TOS (nTOS) is often conservative. Data are limited, therefore there is no conclusive evidence that any one treatment method or combination is more effective. Surgery in nTOS is considered for refractory cases only. Anticoagulation and surgical decompression remain the treatment of choice for vascular versions of TOS.

Conclusions
The most common form of TOS is neurogenic. The most common symptoms are pain and paresthesias of the head, neck, and upper extremities. Diagnosis of nTOS is clinical, and the best screening test is the ULTT. There is no conclusive evidence that any one treatment method is more effective for nTOS, given limitations in the published data. Surgical decompression remains the treatment of choice for vascular forms of TOS.