Axial SpA is a form of inflammatory arthritis that most commonly affects the joints of the spine and pelvis. Common features of spondyloarthritis include inflammatory back pain, as well as pain and inflammation in the peripheral joints, the digestive tract or eyes.
Nowadays, patients with axSpA are usually classified in two groups:
i) Patients with radiographic axSpA also known as ankylosing spondylitis (AS), who have developed substantial damage of the pelvis visible on radiographs, and
ii) Patients with non-radiographic axSpA, who do not have damage visible on radiographs but do have other symptoms specific for axSpA.