What is the characteristic first symptom in ankylosing spondylitis?

• A. Knee synovitis
• B. Low back pain at rest
• C. Cervical pain
• D. Hand small joint synovitis

Answer: (B)

Inflammatory back pain in the axial skeleton is the hallmark early presentation of ankylosing spondylitis. It tends to be insidious and chronic, often starting in younger adults, with morning stiffness lasting tens of minutes to over half an hour and night pain. A key feature is that it improves with movement and activity and NSAIDs, rather than worsening with activity. Pain that is prominent in the low back and is present at rest fits this inflammatory pattern. Peripheral joint involvement like knee or small hand joints usually appears later in the disease, and cervical pain, while possible, is not the defining initial symptom. So the description of low back pain that is worse with rest aligns best with the inflammatory back pain that characterizes early ankylosing spondylitis.