AS Inflammation: MRI

Sacroiliitis is a condition where one or both of the sacroiliac joints become inflamed. It is often misdiagnosed as lower back pain. Learn more.

SAN DIEGO – New studies offer insight into specificity of the scans.
Inflammation shown on MRI of the sacroiliac joint (MRI-SI) is prevalent in axSpA (±30%), but the…
Bone marrow edema (BME) around the sacroiliac joints is common, even in normal people, more so among athletes. It is not diagnostic of AS.
To improve specificity, a higher SPARCC score (5 or more) and deep lesions (BME extending more than 1cm deep to the articular surface) should prove more diagnostic.

 (2) Bone Marrow Edema May be Found in Normals, Athletes and Military Recruits

Effect of mechanical stress on magnetic resonance imaging of the sacroiliac joints: assessment of military recruits by magnetic resonance imaging study


MRI of the sacroiliac joints in spondyloarthritis: the added value of intra-articular signal changes for a ‘positive MRI’

Intra-articular MRI signals (synovitis, fluid, ankylosis) of the sacroiliac joints can greatly enhance the specificity (diagnostic probability) of AS, even without the presence of bone marrow edema (BME), and more so with BME.