Which statement about the onset of inflammatory back pain is true?

Which statement about the onset of inflammatory back pain is true?

• A. Onset before age 40 with morning stiffness greater than 30 minutes.
• B. Onset after age 50 with rapid relief with activity.
• C. Onset in childhood with no morning stiffness.
• D. Onset in adulthood with immediate relief after NSAIDs.

Answer: (A)

Inflammatory back pain typically starts in younger people and features morning stiffness that lasts for more than 30 minutes. This combination—early onset and prolonged morning stiffness—points to an inflammatory process such as axial spondyloarthritis rather than mechanical strain. The other descriptions describe patterns less consistent with inflammatory back pain: onset after 50 is more common with degenerative changes; childhood onset without morning stiffness is unlikely for inflammation; and while NSAIDs often help, immediate relief is not the defining feature. So, onset before age 40 with morning stiffness over 30 minutes best matches the inflammatory pattern.