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What is A 65-year-old man had H/o of back pain since 3 months. ESR is raised. He also has dorso-lumbar tenderness on examination and mild restriction of chest movements. On X-ray, syndesmophytes are present in veebrae. Diagnosis is: and explain in detail?
Ankylosing hyperostosis Ankylosing spondylitis Age Elderly Young Sacroilitis Absent Always present Chest expansion Mild restriction Marked but not reliable in elderly Tenderness Dorso-lumbar Sacroiliac ESR Normal to mild rise High Syndesmophytes Present Present