What are conventional image findings in SpA?

Conventional Radio (not helpful early, structural changes reflect changes by inflammation not inflammation itself, we may get radiographic sacroilitis [blurring of cortical margins of subchondral bone, erosions and sclerosis, joint space appears wider than fibrous, bony ankylosis] X ray has a New York grading system [ I sus, II evidence of erosion/sclerosis, III erosions and early ankylosis, IV total ankylosis, sensitivtiy first year 0%, after 10 years 60%, in spine we see squaring of vertebra secondary to erosions, vertebral enthesitis may cause sclerosis of upper and lower vertebra appear shiny corners romanus sign, syndesmophyte formation, bamboo spine