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Medicine

Joint Inflammation

Quick fact

The word 'inflammation' comes from the Latin 'inflammare', meaning 'to set on fire', and the four classical signs—redness, swelling, heat, pain—were described by the Roman physician Celsus nearly 2,000 years ago.

Why this is interesting

You twist your ankle and it swells up, turns red, and feels hot—but why does the body make a simple injury feel like a fire?