Rubor (redness), 2. Dolor (pain), 3. Calor (increased heat), 4. tumor (swelling).
Inflammation is the response of our body tissue to harmful stimuli. Redness, pain, increased heat and swelling are the four cardinal signs of an inflammatory response. Although loss of function is sometimes added with these four as the fifth sign of inflammatory response.
The cardinal signs of inflammatory response :
The chart below shows the cardinal signs and how they occur (physiologic rationale) :