Which option best describes acute on chronic pain?

• A. New injury in setting of chronic pain
• B. Pain that lasts only a few minutes
• C. Pain without any injury
• D. Pain caused by emotional factors

Answer: (A)

Acute on chronic pain describes a sudden, new pain flare caused by an acute event occurring in someone who already has chronic pain. The defining idea is an identifiable acute injury or tissue-damage process superimposed on a baseline chronic pain condition, leading to higher intensity or a different pain pattern than usual. A new injury in someone with chronic pain fits this description perfectly because it introduces an acute nociceptive or inflammatory process on top of the existing pain. The other options don’t capture that combination: pain lasting only a few minutes sounds like a transient acute pain without a chronic background; pain without any injury could be chronic pain by itself without a new acute component; pain due to emotional factors points to psychosocial contributors rather than an acute superimposed event. Recognizing this distinction helps clinicians diagnose the new acute issue while still managing the underlying chronic pain.