The cardinal signs of inflammation (also known as Celsus' signs) are:
Mnemonic-
RTDC (Root, Trunk, Division, Cord)
RTDC (Rubor, Tumor, Dolor, Calor)
1. Rubor (Redness) – Due to increased blood flow (hyperemia) from vasodilation.
2. Tumor (Swelling) – Results from fluid leakage (edema) due to increased vascular permeability.
3. Dolor (Pain) – Due to chemical mediators like bradykinin and prostaglandins stimulating nerve endings.
4. Calor (Heat) – Caused by increased blood flow and metabolic activity in the inflamed area.
5. Functio laesa (Loss of function) – Described later by Virchow, this refers to impaired function due to pain and swelling.