Rethinking imaging in axial spondyloarthritis: toward diagnostic maturity.

Imaging, particularly magnetic resonance imaging (MRI) scans of the sacroiliac joints, has become central in the evaluation of axial spondyloarthritis (axSpA), partly due to the absence of reliable biomarkers and variable human leukocyte antigen B27 (HLA-B27) prevalence. However, its increasing use as a standalone diagnostic tool represents a conceptual shift that risks undermining clinical reasoning. This viewpoint critically examined the specificity and limitations of imaging findings and highlighted that lesions such as bone marrow oedema and structural changes may also occur in non-SpA populations, including healthy individuals and those with mechanical back pain. Misinterpretation, rather than intrinsic imaging limitations, is a major driver of diagnostic error. In this viewpoint it is argued that imaging should serve a supportive and prognostic role, integrated within a broader clinical framework that includes patient history, clinical features, and laboratory data. Overreliance on imaging contributes to diagnostic inflation, particularly in non-adiographic and atypical populations, with implications for patient care and healthcare systems. Emerging tools such as artificial intelligence may amplify these challenges if not carefully validated. Recentring clinical reasoning, promoting multidisciplinary collaboration, and ensuring imaging is requested and interpreted within an appropriate clinical context are essential steps forward. Ultimately, imaging should inform but not replace clinical judgement in the diagnosis of axSpA.