The role of magnetic resonance imaging in the evaluation of peripheral nerves following traumatic lesion: where do we stand?

BACKGROUND: Peripheral nerve injury is a common and important cause of morbidity and disability in patients who have suffered a traumatic injury, particularly younger people. Various different injuries can result in damage to specific nerves. In patients with multiple trauma, the prevalence of peripheral nerve injury is estimated at 2.8%, but can reach 5% with the inclusion of brachial plexus involvement. Physical examination, as well as the origin and location of the trauma, can indicate the nerve involved and the type of nerve damage. However, the depth and severity of damage, and the structures involved often cannot be determined initially, but depend on longer periods of observation to reach a definitive and accurate diagnosis for which treatment can be proposed. Current approaches to locate and assess the severity of traumatic nerve injury involve clinical and electrodiagnostic studies. From a clinical and neurophysiological point of view, nerve injuries are classified in an attempt to correlate the degree of injury with symptoms, type of pathology, and prognosis, as well as to determine the therapy to be adopted. OBJECTIVES: MRI in the diagnosis of traumatic peripheral nerve injury has increasingly been used by surgeons in clinical practice. In this article, we analyze the use of magnetic resonance (MR) for the evaluation of traumatic peripheral nerve diseases that are surgically treatable. We also consider basic concepts in the evaluation of technical and MR signs of peripheral nerve injuries. MATERIALS AND METHODS: Studies were identified following a computerized search of MEDLINE (1950 to present), EMBASE (1980 to present), and the Cochrane database. The MEDLINE search was conducted on PUBMED, the EMBASE search was conducted on OVID, and the Cochrane database was conducted using their online library. A set was created using the terms: 'traumatic', 'nerve', and 'resonance'. RESULTS: The included articles were identified using a computerized search and the resulting databases were then sorted according to the inclusion and exclusion criteria. This yielded 10,340 articles (MEDLINE, n = 758; EMBASE, n = 9564; and Cochrane, n = 18). A search strategy was then built by excluding articles that only concern plexus injury and adding the terms 'neuropathies', 'DTI' and 'neurotmesis'. In total, seven studies were included in the review effectively addressing the role of MRI in the evaluation of traumatic peripheral nerve injury. We extracted all relevant information on the imaging findings and the use of magnetic resonance in trauma. We did not include technical or specific radiological aspects of the imaging techniques. CONCLUSIONS: These seven articles were subsequently evaluated by analyzing their results, methodological approach, and conclusions presented.

Lesões do plexo braquial / Brachial plexus injury

A lesão do plexo braquial acarreta grave disfunção no membro superior. Pode ser resultante de qualquer trauma com energia suficiente para tracionar, romper ou até avulsionar as raízes nervosas diretamente da coluna cervical. Os mecanismos mais comuns são os acidentes de motocicletas em homens jovens. A abordagem inclui minuciosa anamnese, com identificação do mecanismo e energia do trauma, exames eletrofisiológicos e de imagem. O tratamento especializado e precoce vai oferecer as melhores chances de recuperação. Recentemente, a contribuição da microcirurgia e as técnicas de neurotização (transferência de um nervo funcionante oriundo de uma raiz nervosa sadia e anastomosada com o coto distal do nervo lesado) têm demonstrado resultados satisfatórios. O artigo revisa a etiopatogenia das lesões de plexo braquial, o diagnóstico e as condutas atuais no tema

Brachial plexus injury causes severe upper limb dysfunction. It may result from any trauma that is strong enough to pull, break up or even avulse nerve roots directly from the cervical spine. The most common mechanisms are motorcycle accidents in young men. The approach includes thorough history taking, identifying the mechanism and energy of trauma, and electrophysiological and imaging examinations. Early specialized treatment will offer the best chances of recovery. Recently, the contribution of microsurgery and the techniques of neurotization (transfer of a functioning nerve from a healthy nervous root that is anastomosed with the distal stump of the injured nerve) have shown satisfactory results. The article reviews the etiopathogeny, diagnosis and current approaches to brachial plexus injuries