4. Venous Insufficiency
Chronic venous insufficiency is another possible explanation. This occurs when the valves in the veins of the leg do not work properly, making it hard for blood to return to the heart. As a result, blood pools in the legs, leading to swelling, redness, heaviness, and sometimes skin changes or ulcers. Unlike DVT or cellulitis, venous insufficiency usually develops gradually, but in some cases, the symptoms may suddenly worsen.
