Venous leg ulcers, also known as venous stasis ulcers, can result when a perforator vein valve or the calf muscle pump does not work properly and causes the blood to back flow. This is called "reflux." Back flow causes increased pressure in the perforator vein and surrounding tissue. The leg becomes swollen from this increased pressure. This pressure causes skin changes such as discoloration, darkening, tightening and hardening. If an external injury, bump, or even a slight scratch affects this damaged tissue, an ulcer can form.

Most refluxing perforator veins can be treated with a painless injection of a medication followed by one to two weeks of compression with stockings.