Dynamic neuromusculoskeletal ultrasound documentation of brachial plexus/thoracic outlet compression during elevated arm stress testing.

BACKGROUND The diagnosis and validation of thoracic outlet syndrome/brachial plexopathy (TOS) remains a difficult challenge for surgeons, neurologists, and radiologists. This is due to the fact that the responses of standard elevated arm stress tests can be considered somewhat subjective and can vary. Therefore, non-vascular TOS cases are presently diagnosed clinically, and any objective diagnosis has been controversial. METHODS This is a technique paper describing the use of dynamic neuromusculoskeletal ultrasound to assist in the diagnosis of thoracic outlet/brachial plexus pathology. We propose a new way to observe the brachial plexus dynamically, so that physical verification of nerve compression between the anterior and middle scalene muscles can be clearly made at the onset of clinical symptoms. This gives a way to objectively identify clinically significant brachial plexus compression. RESULTS Dynamic testing can add objective analysis to tests such as the elevated arm stress tests and can correlate the onset of symptoms with plexus compression between the anterior and middle scalene muscles. With this, the area of pathologic compression can be identified and viewed while performing the dynamic testing. If compression is seen and the onset of symptoms ensues, this is a positive confirmatory test for the presence of TOS and a clinically significant disease. CONCLUSIONS This paper offers a simple, objective, and visual diagnostic test that can validate the presence or absence of brachial plexus compression during arm elevation in patients with brachial plexus injury and thoracic outlet syndrome.