Purpose of review: Both MRI and plain radiography are used to assess sacroiliitis. A weakness of radiography - apart from its inability to detect early disease - is reader variability. On the contrary, experience with MRI is relatively limited by comparison.
Recent findings: This review summarizes recent advances in sacroiliac joint imaging using radiography and MRI in spondyloarthritis.
Summary: Observer variation in reading radiographs of sacroiliac joints remains an unresolved issue. In recent years, more studies on MRI in the diagnosis of axial spondyloarthritis have become available. Incorporating structural lesions in the sacroiliac joint and spine and inflammatory lesions in the spine in the definition of a positive MRI are hot topics in research.