Redness (Rubor)
- Cause: Increased blood flow to the area, leading to vasodilation and leakage of red blood cells into the tissue.
Swelling (Tumor)
- Cause: Increased permeability of blood vessels allows fluid and protein to leak into the tissue, leading to oedema.
Heat (Calor)
- Cause: Increased blood flow to the area leads to an increase in temperature.
Pain (Dolor)
- Cause: Activation of nociceptors, pain receptors in the affected tissue, by inflammatory mediators such as histamine and prostaglandins.
Loss of function (Functio Laesa)
- Cause: The combination of pain and tissue damage can lead to a decrease in the function of the affected area.