Sacroiliac joints imaging in axial spondyloarthritis.

Imaging of the sacroiliac joints is the key point in diagnosing and classifying spondyloarthritis. Since the integration of MRI criteria to the Assessment of Spondyloarhtitis Society (ASAS) classification in 2009, the attention was focused on the presence of bone marrow edema to characterize sacroiliitis. However, returning to basics and analysing structural signs is of utmost importance to avoid overdiagnosis of spondyloarthritis.