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Axial spondyloarthritis (AxSpA) is a type of inflammatory arthritis that primarily affects the spine including the sacroiliac (SI) joint located at the base of the spine. Over a lifetime, the AxSpA can lead to the fusion of the vertebrae and crippling effects on quality of life. This condition is

subdivided into two forms: ankylosing spondylitis (AS) and non- radiographic axial spondyloarthritis (nr-axSpA). While AS is usually

diagnosed using X-ray images that show irreversible bone damage, nr- AxSpA is more difficult to diagnose. In both cases, early detection of

disease will best prevent disease progression and preserve quality of life. An additional form of imaging, magnetic resonance imaging (MRI), has been valuable in developing more effective AxSpA classification criteria by allowing earlier identification of inflammation within the spine. However, the classification criteria remain under scrutiny due to the lack of specificity in biological markers and physical examinations. The Classification of Axial Spondyloarthritis Inception Cohort (CLASSIC) study aims to validate the performance of the current classification criteria in a prospective cohort of patients presenting to rheumatologists with low back pain. The study achieves these goals by assessing individual subjects in a step-wise manner that blinds the site primary investigator (PI) to the subject’s information.

Publication Date

Spring 2022


Conducting research in the Department of Rheumatology at the Cleveland Clinic

CLASSIC Clinical Trial: A Methods Study in Unexplained Back Pain