The lower leg is where venous disease shows itself, and it works against the wound continuously, rather than being an obstacle that can simply be removed.
Here is how it works. The veins have one-way valves that keep blood flowing up toward the heart. When these valves become weak or the veins become scarred and blocked, blood flows backward and pools in the legs. This is venous insufficiency, and it leads to high pressure in the lower leg veins. The increase in pressure and buildup of fluid makes it harder for nutrients and oxygen to get to tissues. Cells die, tissue is damaged, and a wound can form.
The pressure that made the wound is still there while the wound is trying to close. That is why, to help treat a venous ulcer, the high pressure in the leg veins needs to be relieved — and why the treatment is aimed at the pressure rather than at the wound surface.
Four things help: wear compression stockings or bandages every day as instructed; put your feet above your heart as often as possible; take a walk or exercise every day; take medicines as directed. If ulcers do not heal well, your provider may recommend certain procedures or surgery to improve blood flow through your veins.
Compression is the one most often not done as instructed, and what it does is specific: it helps prevent blood from pooling, reduces swelling, helps with healing, and reduces pain.
But a lower leg wound is not necessarily venous, and that matters before any compression goes on. Most ischemic ulcers occur on the feet and legs, and for those, do not wear compression stockings or wraps unless told to by your provider, because they may restrict blood flow.
Beyond the wound type, the general list applies: infection, diabetes, poor circulation due to damage to arteries or veins, nerve damage, bone infection, immobility, a weak immune system, poor nutrition, excess alcohol use, smoking, and a foreign body. And the numbers: a wound that has not started to heal in 2 weeks, or not completely healed in 6, is called a non-healing wound. Venous ulcers can be slow to heal.