some nice explanations of definitions https://www.rheumatologyadvisor.com/home/topics/spondyloarthritis/asas-working-group-updates-definitions-of-mri-lesions-in-sacroiliac-joints-with-spa/ The Assessment of Spondyloarthritis International Society (ASAS) magnetic resonance imaging (MRI) working group revised and created new definitions for both inflammatory and structural MRI lesions in spondyloarthritis (SpA), according to research results published in the Annals of the Rheumatic Diseases. Investigators highlighted the growth of clinical understanding of MRI lesions in the sacroiliac joint in the past decade. As a result, the ASAS MRI working group conducted a consensus update and determined the necessity of new or standardized definitions for MRI lesions in the sacroiliac joint in patients with SpA. A total of 20 rheumatologists and 5 radiologists in the working group participated in the consensus exercises; they used MRI scans of patients recruited into the ASAS classification cohort for the exercise. The working group consensus evaluated the overarching recommendations pertaining to optimal interpretation of MRI lesions in the sacroiliac joint. These definitions were then categorized as either lesions indicating signs of activity or structural lesions. 👉Lesion Definitions Indicating Signs of Activity Bone marrow edema: This definition was not revised. Capsulitis: The wording of this definition was revised to clarify its location. Joint space enhancement: This new definition, replacing the original definition of synovitis, applies only to contrast-enhanced sequences. Researchers considered this new definition necessary because of the observation that the synovium was only present at the perimeter of the lower third of the cartilaginous portion of the joint.

Challenge of the week! Post something new that you learned this week (about MSK obviously or related).