Veins carry blood from the legs to the heart, against gravity. One-way valves in these veins prevent the blood from falling back into the lower leg. When these valves malfunction, blood begins to pool in the legs, mostly around the ankles. This pooling of blood causes increased pressure that leads to heaviness, nagging pain, and throbbing all of which worsen towards the end of the day. Conversely, elevating the legs or even just sitting down relieves the heaviness and pain. As the condition worsens, some patients develop a wet seeping wound/ ulcer, usually around the ankle.