Imaging assessment of enthesitis in spondyloarthritis.

Enthesitis, defined as the inflammation of the origin and insertion of ligaments, tendons, aponeuroses, annulus fibrosis, and joint capsules, is a hallmark of spondyloarthritis (SpA). New imaging techniques including magnetic resonance imaging (MRI), ultrasonography, and positron emission tomography with computed tomography using 18F-fluorodeoxyglucose capable of detecting morphological and metabolic abnormalities and monitoring disease activity have improved the assessment and management of enthesitis of SpA.