Table 1.

New York criteria for sacroiliitis.

Grade	Evaluation
0	Normal sacroiliac joints
I	Suspected changes – blurry margins of the joint space
II	Minimal changes – visible periarticular sclerosis, single erosions; only when the joint space is blurred, with no change in joint space width
III	Advanced changes – numerous erosions, distinct periarticular sclerosis, widened articular space, possible partial bony ankylosis
IV	Total bony ankylosis