Radiographic imaging modalities for perinatal brachial plexus palsy: a systematic review

Diagnostic accuracy of MRI for detecting nerve injury in brachial plexus birth injury

OBJECTIVES

To determine the diagnostic accuracy of MRI for diagnosing nerve injury in brachial plexus birth injury (BPBI).

METHODS

Electronic databases were searched from inception to February 15, 2023 for studies reporting the accuracy of MRI (index test) compared to surgical exploration (reference standard) in detecting the target conditions of: root avulsion, any nerve abnormality, and pseudomeningocele (as a marker of root avulsion) in children with BPBI. Meta-analysis using a bivariate model was performed where data allowed.

RESULTS

Eight studies met the inclusion criteria. In total, 116 children with BPBI were included. All included studies were at risk of bias. The mean sensitivity and mean specificity of MRI for detecting root avulsion was 68% (95% CI: 55%, 79%) and 89% (95% CI: 78%, 95%), respectively. Pseudomeningocele was not a reliable marker of avulsion. Data were too sparse to determine the diagnostic accuracy of MRI for any nerve abnormality.

CONCLUSIONS

At present, surgical exploration should remain as the diagnostic modality of choice for BPBI due to the modest diagnostic accuracy of MRI in detecting root avulsion. The diagnostic accuracy of MRI needs to be close to 100% as the results may determine whether a child undergoes invasive surgery.

ADVANCES IN KNOWLEDGE

Previous research regarding MRI in detecting BPBI is highly variable and prior to our study the overall diagnostic accuracy was unclear. Through conducting a systematic review and meta-analysis, we were able to reliably determine the overall sensitivity and specificity of MRI for detecting root avulsion.

Brachial plexus birth injury: advances and controversies

While there is considerable spontaneous recovery in most cases of brachial plexus birth injury, many children are left with significant problems that may lead to lifelong functional limitations, loss of work and social isolation. Detailed treatment with the right strategy can provide very valuable improvement in function. Over the past few years, the clinical approach to brachial plexus birth palsy has entered a new era in both diagnostic and surgical treatment methods. This article reviews four areas of management, the role of imaging in defining the severity of the injury, the optimal timing of for nerve exploration and reconstruction in appropriate cases, the advantages and potential complications of nerve transfers, and the role of physiotherapy. Available evidence is considered. Although it is difficult to make clear and precise inferences on a subject where there are many variables and considerable uncertainties, some currently accepted views will be summarized.Level of evidence: V.