Post-traumatic brachial plexus MRI in practice

Abstract

Injuries are separated into spinal nerve root avulsions (pre-ganglionic lesions) and more distal rupture (post-ganglionic lesions). The lesions may be associated with different nerve root levels. Spinal MRI is used to diagnose pre-ganglionic lesions, which may be present in the absence of pseudomeningoceles. The other sequences described are used to diagnose post-ganglionic lesions, regardless of the type of lesion. Knowledge that a graftable C5 nerve root is present is important in the treatment strategy. Contrast enhancement in the scalene triangle does not predict the quality of the nerve root (continuous injury with response to peroperative stimulation or division of the root needing grafting). Understanding post-traumatic neuronal injuries to the brachial plexus. Knowing how to look for spinal MRI abnormalities and post-ganglionic abnormalities.

Pseudomeningocele From Brachial Plexus Root Avulsion

“…Majority of these forces are secondary to motor vehicle accidents with 1% of major traumas associated with brachial plexus injuries [1,2]. Clinical examination is of key importance as early assessment and establishing neurological stability or deterioration dictates timing and candidacy for surgery [3]. Patients may present with weakness, dysesthesia and headaches.…”

Differentiation of Pre- and Postganglionic Nerve Injury Using MRI of the Spinal Cord

“…Lately MRI, employing high quality myelography sequences, has emerged as an attractive alternative with comparable diagnostic value. [3, 23, 24] The current diagnostic MRI protocols in clinical use are largely based on the imaging of nerve roots, together with the detection of indirect signs of injury. [25, 26] Although constant methodological improvements are being made, due to artifacts and certain interferences, the currently available MRI protocols are yet not considered reliable in the diagnostics of brachial plexus injury.…”

“…[2] The current treatment approach is largely dependent on the level of injury, with a distinction being made between the preganglionic nerve injury to the spinal roots, and the postganglionic nerve injury to the spinal nerves. [3] In the case of the latter injury type, function may either spontaneously return with time or, when loss of nerve continuity occurs, the nerve can be repaired using an autologous nerve transplant, which is normally harvested from the patients leg. Preganglionic avulsion injury is a severe form of preganglionic nerve injury that causes a disconnection between the central and peripheral nervous systems.…”

High resolution neurography of the brachial plexus by 3Tesla magnetic resonance imaging

“…In 25% of the cases, the phrenic nerve is also compromised. 29,30 Klumpke's palsy or distal paralysis occurs due to the avulsion of roots C8 and T1; on some occasions it can affect root C7. It is less common than the proximal variant.…”