Radiological Assessment of Lumbar Fusion Status: Which Imaging Modality is Best Assessing Non-union in Lumbar Spine Pseudarthrosis?

Abstract

Study DesignSystematic Review.ObjectiveTo assess the current literature regarding the accuracy of different imaging modalities and criteria used to assess lumbar fusion, and their correlation with surgical direct observation as the current Gold Standard.MethodsFollowing PRISMA guidelines, we conducted a comprehensive search of PubMed, Embase, Google Scholar, and Cochrane Library, studies were included if they focused on patients with a prior history of lumbar interbody fusion and at least 1 year of radiographic follow-up. The review assessed the sensitivity, specificity, and accuracy of different imaging techniques, and their correlation with surgical findings.ResultsThirteen studies (1989-2019) were reviewed, including 715 patients, common imaging modalities included plain radiographs (53.8%), Computed Tomography (CT) (69.2%), and dynamic radiographs (30.7%). CT appeared as the most utilized modality post-2006. There was substantial variability in diagnostic accuracy, with CT showing high variability in sensitivity and specificity. Descriptive criteria for fusion were widely used, but interobserver agreement was generally low.ConclusionThe review highlights a lack of standardized criteria for assessing lumbar fusion. Despite advancements in imaging techniques, the variability in diagnostic parameters suggests a need for consensus and multicentric studies to stablish reliable, universal criteria for evaluating fusion success.