Ankylosing Spondylitis and Axial Spondyloarthritis

This article summarizes the clinical definition of ankylosing spondylitis and axial spondyloarthritis, discusses the pathogenesis of these conditions, and reviews approaches to management. Chronic back pain is common worldwide and is cared for by a variety of providers, but specific, satisfactory treatment is often lacking. Ankylosing spondylitis, an inflammatory disorder that in its extreme form can lead to the bony fusion of vertebral joints, is an uncommon but well-established cause of chronic back pain. During the past decade, ankylosing spondylitis has come to be considered as a subset of the broader and more prevalent diagnostic entity referred to as axial spondyloarthritis. The estimated prevalence of axial spondyloarthritis in the United States is 0.9 to 1.4% of the adult population, similar to that of . . .