Review of the updated definitions and concepts of spinal lesions in axial spondyloarthritis

Spinal imaging may support the diagnosis of axial spondyloarthritis when typical findings are recognized in an appropriate clinical context and it can also indicate disease activity. In May 2022, the definitions for inflammatory and structural spinal lesions in axial spondyloarthritis were updated and validated by the Assessment of SpondyloArthritis international Society (ASAS) magnetic resonance imaging (MRI) working group. The aims of this paper are to demonstrate and describe imaging findings of the spine in patients with axial SpA, including the latest updated definitions by the ASAS, and to show complications in patients with long-standing disease.