Review of the brachial plexus anatomy and its evaluation by imaging

Abstract The brachial plexus is an important anatomical structure composed of roots, trunks, divisions, cords, and terminal branches. For the appropriate evaluation of its components, we must know its anatomical references; these allow us to locate the pathologies in the different imaging modalities. MRI is the imaging evaluation method of choice. We present the protocol used in our center. We can divide brachial plexus pathologies into two main categories: traumatic and non-traumatic. Traumatic pathology is the most common, in which there are findings to determine whether the lesion is preganglionic or postganglionic. Non-traumatic pathology includes post-radiation plexopathy, acute brachial neuritis, primary and secondary tumors, peripheral neuropathies, and thoracic outlet syndrome. In this review, we describe the main characteristics of these pathologies, with representative radiological cases.