Fig. 11From: Frequency of inflammatory back pain and sacroiliitis in Egyptian patients with rheumatoid arthritisa, b Flow chart showing the classification steps for ankylosing spondylitis and axial spondyloarthritis in the 100 rheumatoid arthritis patients. SI, sacroiliitis; mNY, modified New York; ASAS, Assessment in SpondyloArthritis international Society; MRI, magnetic resonance imaging; SIJ, sacroiliac joint; SpA, spondyloarthritis; IBP, inflammatory back pain; HLA-B27, human leucocyte antigen-B27Back to article page