Foot Ulcer

Wound and Ulcer Conditions· Also known as: ulcer on the foot, foot soreUpdated Nov 2026

Reviewed by Andrew Schox, BSc(Hons) PGradDipPod MPod, November 2026

At a Glance

A foot ulcer is a sore on the foot, where the skin has broken open, and it heals slowly. Among people with diabetes, roughly 6.3 per cent have one at any given time. The main sign is a sore that doesn't heal, and it may not hurt at all. Proper care from your podiatrist and regular foot checks matter. Increased pain or throbbing, heat, new or spreading redness or swelling, discharge, a new smell, or fever or flu-like symptoms can be signs of infection, and a hot, red, swollen foot could be a Charcot foot.

What is it?

A foot ulcer is an open sore or break in the skin of the foot, below the ankle. It is slow to heal. It may be shallow, in the top layer of skin, or it may go deep into the tissue of the foot.

Many things can cause one, including pressure, rubbing, injury, moisture, a change in the shape of the foot, diabetes, nerve damage and poor circulation (poor blood supply to the foot). Foot ulcers are most often linked to diabetes, pressure or poor circulation.

Who does it affect?

Most of what is known is about adults with diabetes, so the figures below are for them. They may not apply to ulcers from other causes or to children, and estimates vary between regions.

About 6.3 per cent of people with diabetes worldwide have a foot ulcer at any one time. This ranges from about 3.0 per cent in Oceania to 13.0 per cent in North America. Each year, about 2 per cent of people with diabetes develop one. Over a lifetime, the risk is about 19 to 34 per cent.

Some things are linked to a higher chance of an ulcer: older age, being male, having diabetes for longer, high blood pressure, smoking, and diabetes problems in the kidneys, nerves or eyes. Ulcers are a little more common in type 2 diabetes (6.4 per cent) than type 1 (5.5 per cent), and in men (4.5 per cent) than women (3.5 per cent). These are links, not proven causes.

Signs and symptoms

The symptom seen most often is an open wound that stays unhealed. Redness, swelling, soreness or tenderness often accompany it. Some ulcers hide under a thick patch of hard, discoloured skin (callus), so you may not see them at first.

A foot ulcer may not hurt at all. This is why it is easy to miss. If you have diabetes, look at your feet every day for cuts, sores, red spots, swelling, blisters and calluses. Looking at your feet each day lets you catch problems sooner, before they worsen.

What causes it?

Foot ulcers usually come from several causes acting together.

The most important is nerve damage (neuropathy). When you lose feeling in your feet, small cuts, rubbing or infection can go unnoticed. Nerve damage can also change the shape of the foot, such as hammer toes or a claw foot. This creates spots of high pressure that lead to calluses and then ulcers.

Poor circulation, also called peripheral artery disease, is another common cause. It is thought to play a part in about one-third of foot ulcers. Among people with diabetes, it is put at about half. It also makes ulcers more likely to come back.

Infection often follows. It develops in about 50 to 60 per cent of ulcers and is the main thing that damages feet with diabetes.

How is it diagnosed?

Your podiatrist or GP will look at the ulcer and note where it is, how big and deep it is, and what is coming from it.

They will test the feeling in your feet with a fine nylon thread (a 10-g monofilament) and usually one other test, such as a tuning fork. Not feeling the thread can point to nerve damage.

They will check your circulation: the pulses in your foot, the ankle-brachial index (a blood pressure check at your ankle) and, if you have diabetes and peripheral artery disease, a test such as toe pressure. Any ulcer that isn't healing needs a circulation check.

A probe-to-bone test checks how deep the ulcer is and whether the bone may be infected.

Scoring tools such as SINBAD describe the ulcer in a standard way. They are aids, used alongside your practitioner's judgement.

Treatment

Most of this advice is for adults with diabetes.

Looking after it at home

Don't treat a foot ulcer yourself. Keep the dressing dry, as getting it wet can stop healing or let bacteria in. Wear the offloading device or footwear your podiatrist gives you, as instructed. Go to every wound care visit.

Treatment from your podiatrist

Offloading (taking pressure off the ulcer) is arguably the most important step. For a nerve-damaged ulcer under the front or middle of the sole, the first choice is a knee-high device you can't remove. A removable knee-high or ankle-high device is next if that isn't suitable. Ulcers with poor circulation or infection need a specialist team's assessment first.

Debridement (removing dead or unhealthy tissue) may be repeated at least weekly. Treatment also includes controlling infection, dressings, and treating poor circulation if needed. Mild and most moderate infections are treated with antibiotic tablets; severe infections, or moderate ones with other health conditions, start with antibiotics given by injection or drip.

Your foot care involves a multidisciplinary team, for example podiatry, vascular, orthotics and diabetes care.

Other options

If an ulcer hasn't healed with standard care, a specialist may suggest an add-on, such as sucrose octasulfate dressings, suction treatment after surgery, placenta-based products, a patch made from your own blood cells and clotting protein, or oxygen treatment. These are used only where standard care alone hasn't worked. They don't replace offloading, infection control and circulation checks, and some have caused serious side effects.

Recovery

Foot ulcers can be slow to heal, and typical healing times aren't clear yet. Typical healing times aren't clear yet. In people with diabetes and a foot ulcer, starting treatment late is a risk factor for more lower limb amputations and is linked to longer treatment, larger wounds and poorer healing.

An ulcer can come back, and the risk is highest just after it closes. After healing, about 40 per cent of people have another within 1 year, almost 60 per cent within 3 years and 65 per cent within 5 years.

About 20 per cent of people who develop a diabetes-related foot ulcer need an amputation, and about 10 per cent die within a year of diagnosis. These figures are for adults with diabetes and describe groups, not what will happen to you.

Preventing it

If you have diabetes, regular foot checks are recommended, and how often they are recommended rises with risk level: yearly for very low risk, every 6 to 12 months for low, every 3 to 6 months for moderate, and for example every 1 to 3 months for high. Checks are still needed after an ulcer heals.

Check the tops, soles and between your toes every day, using a mirror if needed. The Australian guideline recommends structured education on foot care and footwear for people at increased risk.

What can make it serious?

You have a foot wound, ulcer or infection and also feel very unwell, with confusion or slurred speech, severe shivering or muscle pain, severe breathlessness, mottled or discoloured skin, or little or no urine (possible sepsis).
Redness from a wound, sore or infection is spreading into your foot or leg, or red streaks run up from it.
You have a foot wound, ulcer or infection, or a red, hot, swollen foot, and also have a fever, chills, a fast heartbeat or feel unwell.
Your foot, or a patch of skin on your foot or leg, becomes red, hot, swollen and painful.
You have diabetes or poor circulation and signs of infection in your foot, toe or nail, such as redness, warmth, swelling, pus, a bad smell or more pain.
You have diabetes or poor circulation and a foot infection that is spreading fast, with a fever, and you feel very unwell.
You have diabetes, poor circulation or reduced feeling in your feet and notice a new wound, sore, blister or colour change on your foot, or a sore that isn't healing.
You have diabetes and a foot problem, and you also feel unwell, or your foot swells quickly.
You have diabetes or reduced feeling in your feet and one foot becomes red, hot or swollen, or suddenly changes shape, even if it doesn't hurt (possible Charcot foot).
You have constant pain in your foot or toes that is worse at night or when your legs are raised, and eases when you hang your leg down (this can be a sign of poor circulation).
The skin on your toes or foot turns dark or black, or a wound turns black and smells bad.
You have pain in a bone with a fever.
An infection is getting worse, with more pain, redness, swelling or pus, but the redness isn't spreading and you feel well.
A wound or sore on your foot or leg hasn't started to heal after two weeks, or keeps coming back.
Your foot ulcer is being treated but isn't getting better (ask about a review by the foot team).

Frequently asked questions

What kinds of foot ulcer are there, and why does the type matter?

Foot ulcers in people with diabetes are grouped by cause: nerve damage (neuropathic), poor circulation (ischaemic), both together (neuroischaemic), or pressure. Your care team uses the type to orient your treatment.

What are the main steps in looking after a foot ulcer?

Care usually covers several steps together: treating the underlying cause, controlling infection, managing poor circulation, removing dead tissue (debridement), dressing the wound and taking pressure off the foot (offloading). Your foot care team will explain how each one applies to you.

Can I look after a foot ulcer on my own?

It is best not to. Treatment of an ulcer is usually guided by a podiatrist or your foot care team, and following their advice forms part of that treatment. If you notice a change such as pain or throbbing, a hotter foot, new redness, swelling, discharge, a new smell, a rash or flu-like symptoms, this may be a sign of infection.

Why is it worth asking about my circulation?

Poor circulation affects the chance of healing and changes how an ulcer is treated. A circulation check helps your team choose the right care, so ask whether yours has been checked, especially if the ulcer isn't healing.