Right sacroiliitis is grade 1 (suspicious of sacroiliitis with no clearly specific abnormality). Left sacroiliitis is grade 2 (minimal changes of sacroiliitis with some loss of definition at the edge, some sclerosis, and perhaps minimal erosions and some joint space narrowing).
Courtesy of Xenofon Baraliakos, Rheumazentrum Ruhrgebiet Herne, Ruhr-Universität, Herne, Germany.
