A foot wound that never quite closes is one of those things you shouldn't let slide. When an ulcer stalls week after week, there is almost always a reason, and a very common one — especially in people with diabetes — is poor blood flow.
Not closing is not normal
A healthy wound shows visible improvement within days and closes within a few weeks. If a foot ulcer isn't progressing, or gets worse, it's not a matter of being patient: it's a sign that something is preventing healing and needs to be investigated.
Why it won't heal
To close, a wound needs enough blood to reach it. Blood carries the oxygen and the elements that repair tissue and fight infection. If the arteries in the leg and foot are narrowed — what we call an ischemic foot — that supply is not enough and the wound stays stalled.
In people with diabetes this is especially relevant, because the loss of blood flow is compounded by loss of sensation, which means the injury can go unnoticed. We cover this in the article on diabetic foot and poor circulation. That's why it is extremely important to take exceptional care of the feet, keep active watch, and wear roomy footwear that doesn't cause rubbing.
When to seek care without delay
Pain at rest, a bad smell or discharge, spreading redness, or fever. These are signs of infection or a significant lack of blood flow: don't wait.
How it is assessed
The key is to check whether blood is reaching the foot. To do this, the pulses are assessed, the ankle-brachial index is measured, and a Doppler ultrasound is performed; if a detailed view of the arterial map is needed, CT angiography or arteriography is used. With this information, it can be determined precisely whether the wound isn't closing because of poor blood flow, and where the problem lies.
When faced with a foot ulcer that won't close, the first step is to evaluate the ulcer itself and examine the patient's pulses. If impaired circulation in the limb is confirmed, it is imperative to assess the need for revascularization.
What can be done
If the ulcer isn't closing because of poor blood flow, the decisive step is to restore it. Revascularization can be done by endovascular means (catheterization, angioplasty, stent, among others) or with surgery using bypass or other techniques, depending on the case. This is combined with proper wound care, treatment of infection if present, and relieving pressure on the area. You can find more context on the page about diabetic foot.
In summary
A foot ulcer that won't close should be investigated, because it can indicate poor blood flow. Without enough blood supply, the wound will struggle to heal no matter how well it's cared for. Assessing circulation is a priority, and if blood flow is lacking, restoring it is what allows or speeds up healing. If there are signs of infection or pain at rest, seek care without delay.