Leg ulcer types come down to three common causes: veins that no longer move blood out of the leg, arteries that no longer bring enough blood in, and pressure on a foot that has stopped feeling it. Between them they account for the large majority of open sores below the knee, and separating them decides the treatment, because what heals one can set another back.
The instinct is to compare photographs, which turns out to be the least reliable route available. Where the sore sits, what the skin around it is doing, and what the pain does when the leg goes up separate the three far more dependably than the surface of the wound ever does. This guide covers each type, the checks that tell them apart, what a clinic adds that home judgment cannot, and the one safety point that makes the answer genuinely urgent.
On this page
- What are the three main leg ulcer types?
- Why appearance misleads so often
- Position and pain: the check that separates them
- The three types side by side
- When a leg ulcer is more than one thing
- How a clinic works out which it is
- Why the label changes the treatment
- When a leg ulcer becomes urgent
- What you can do
- What to avoid
- Living with a leg ulcer
- When to get it seen
- Common questions
- The takeaway
What are the three main leg ulcer types?
Venous, arterial and diabetic. The third is also called neuropathic, meaning driven by nerve damage. Each begins with a different failure in the leg, which is the reason each ends up with a different plan.
A venous ulcer is the most common by a wide margin. Small valves inside the leg veins normally stop blood sliding back down between heartbeats. When they leak, pressure builds in the lower leg, fluid and blood cells seep into the tissue, and the skin around the ankle gradually gives way. A knock or an insect bite may be what opens it, but the pressure behind it is what keeps it open.
An arterial ulcer is the mirror image. Arteries narrowed by fatty deposits deliver less blood than the tissue needs, and skin living on a thin supply cannot repair itself after minor damage. The underlying condition is peripheral arterial disease, and a sore on the foot is sometimes the first sign anyone notices. These wounds tend to be painful out of all proportion to their size.
A diabetic foot ulcer starts with sensation. Long-standing diabetes can damage the nerves that report pressure and pain, a problem called neuropathy. A shoe that rubs, a seam, a small stone, a walking pattern that loads one spot: none of it registers, so nothing changes, and the tissue under that spot breaks down from the inside out. The name misleads in one respect, since these wounds sit on the foot far more often than on the leg itself.
Less common causes exist: inflammation of small blood vessels, certain blood disorders, some medications, and occasionally a skin cancer treated as an ulcer for months. An open sore fitting none of the usual patterns, or one making no progress after a fair stretch of correct treatment, is a reason for a clinician to look again and sometimes to take a small tissue sample.
Why appearance misleads so often
Because nearly everything that happens to a wound after it opens changes how it looks, while none of it changes the cause.
Pictures used to teach the difference show textbook examples: a shallow, red, weeping sore at the inner ankle for veins, a small deep crater with sharp borders on a toe for arteries. Real wounds arrive with dressing residue, softened white edges from trapped moisture, dried blood, a layer of yellow dead tissue across the base, or the redness of an infection sitting on top of the original problem. Any of those can make a venous ulcer look arterial, or the reverse.
Depth misleads too. A venous ulcer neglected for a year gets deep; an arterial ulcer caught in its first week is shallow. Size tracks how long a wound has been open and how well it has been managed, and says little about which vein or artery is at fault.
What stays stable is the setting. Position on the limb, the condition of the surrounding skin, whether pulses can be felt at the ankle, whether the foot has normal sensation, and how the pain behaves through the day. Those features belong to the cause and not to the wound, so they survive infection, dressings and time.
Position and pain: the check that separates them
Two questions get most people close. Where is it, and what does raising the leg do to it?
Position first. A sore on the inner side of the ankle, in the area just above the bony bump, is venous territory, and that one location covers a large share of all leg ulcers. Toes, the tip of a toe, the heel, the outer ankle and the front of the shin point toward arteries. The ball of the foot, the underside of a big toe joint, or a heel with a ring of thick hard skin around the opening points to pressure on a foot that has lost feeling.
Then the pain, which is the more telling of the two. A venous leg aches, feels heavy, and is at its worst after a long day standing. Putting the leg up eases it, because elevation drains the pressure causing the ache. Arterial pain does the opposite. Raising the leg takes gravity away from an already weak blood supply, so the pain increases, and letting the leg hang down brings relief. People with advanced arterial disease often sleep in an armchair or with the foot out of the bed, having worked this out for themselves without knowing why it helps.
If putting the leg up settles the ache, that points to veins. If putting the leg up makes the pain worse and hanging it down relieves it, that points to arteries and should be assessed promptly.
The third pattern is the absence of a pattern. A diabetic foot ulcer frequently causes no pain whatsoever, and a wound that should hurt and does not is a finding in itself. Painless open sores on the sole are the reason foot ulcers get discovered by a spouse, a shoe that feels damp, or a stain on a sock. Silence from a wound is not reassurance in a numb foot.
The three types side by side
Read the table as a set of tendencies. Individual wounds break these patterns regularly, and one row on its own settles nothing.
Three rows deserve a word of explanation, because the reasoning behind them is what makes them useful.
The brown staining around a venous ulcer is old blood. Red cells forced out of overloaded veins break down in the tissue and leave iron behind, discoloring the skin permanently in a cuff around the lower leg. The skin often feels tight and woody alongside it, the ankle narrows while the calf stays full, and the leg takes on the shape of an upside-down bottle. None of that develops in a week, so its presence says the vein problem has been there for years.
Cool, shiny, hairless skin with slow-growing nails is the arterial equivalent. Hair follicles and nails are demanding tissues, and when the blood supply drops they are early casualties. A foot noticeably colder than the other one, pale when raised and dusky red when lowered, is describing its own circulation.
The rim of thick hard skin around a diabetic foot ulcer is a record of repeated loading. Skin thickens where it is rubbed, the thickened patch becomes a hard lump pressing inward with every step, and the tissue underneath eventually gives up. That rim also explains why these wounds are deeper than the opening suggests, and why clearing the callus is part of treating them.
When a leg ulcer is more than one thing
Frequently, and this is the part most self-assessment misses.
Vein disease and artery disease share a set of causes and a set of patients, so a good number of people have both at once. The result is a mixed ulcer: it sits at the inner ankle with the brown staining and the swelling of a venous problem, and the arteries feeding that ankle are narrowed as well. Judged on looks it is venous. Treated as purely venous, with firm compression, it can be made worse.
The same overlap runs through diabetic feet. Some are numb with a perfectly good blood supply. Others are numb and poorly supplied at the same time, a combination clinicians call neuroischemic, and it behaves differently from a purely numb foot: it hurts less than an arterial wound should, heals slower than a neuropathic one should, and carries a higher risk than either pattern alone.
Two practical consequences follow. Anyone working out a leg ulcer checks the arteries before deciding anything, including on legs that look obviously venous. And the honest ceiling on what you can conclude at home is probably. Reaching a probable answer is still useful, since it tells you what to describe and what to ask about, but it is not a plan.
How a clinic works out which it is
Mostly by examining the leg the wound is attached to, supported by a small number of tests.
The history comes first and often does half the work. Varicose veins, a previous clot in the leg, a job spent standing, or a pregnancy long ago all point to veins. Cramping calf pain that arrives after a predictable walking distance and disappears with rest, called claudication, points to arteries, as does a history of smoking, angina or stroke. Diabetes, how long it has been present, and whether sensation in the feet has been tested recently point to the third group.
Then the examination. Both legs, compared against each other, above the ankle as well as at the wound: swelling, skin color and texture, temperature, hair, the shape of the calf, and the pulses at the ankle and the top of the foot, felt by hand and confirmed with a handheld Doppler probe that turns blood flow into sound.
The measurement that changes decisions is the ankle-brachial index. A blood pressure cuff reads the pressure at the ankle, another reads it at the arm, and the ankle figure is divided by the arm figure. Around 1.0 to 1.4 is normal. Values of 0.9 or below suggest narrowed arteries, and lower results usually change what compression can safely be applied. Its known weakness is diabetes and kidney disease, where hardened vessel walls resist the cuff and can return a falsely reassuring number, so pressures at the toe are used instead when that is suspected.
Sensation gets tested with a nylon filament pressed against several points on the sole until it bends, applying a known force. Missing that touch at any of the tested spots means protective sensation has gone, and a foot in that state needs different advice from a foot that can still feel a stone in a shoe. Beyond those, an ultrasound scan can map which veins are leaking, further imaging can show where an artery is narrowed, a swab is taken when infection is suspected and not routinely, and a biopsy is reserved for wounds behaving oddly.
Why the label changes the treatment
Because each type has a different obstacle to healing, and dressings address none of them.
Venous ulcers heal when the pressure in the leg veins comes down, and that is done with compression: bandages or purpose-made stockings applied firmly enough to push fluid back out of the leg and help the calf muscle pump blood upward. Walking and ankle movement do more than they appear to for the same reason. Where leaking veins can be closed by a minor procedure, that is aimed less at the current wound and more at the odds of a new one appearing later.
Arterial ulcers heal when blood reaches them, and until then little else has much effect. The main question is whether the narrowed artery can be opened or bypassed, which means a vascular assessment and sometimes a procedure. Dressings keep the wound clean and protected while that question is answered; they cannot substitute for a blood supply.
Compression that heals a venous ulcer can damage a leg whose arterial supply is already poor, which is why ankle pressures are measured before any compression is applied. This is the most practical reason the distinction matters, and the reason to be wary of compression bought without an assessment.
Diabetic foot ulcers heal when the load comes off the spot. Taking pressure away from the wound is the intervention that decides the outcome, and the options are set out in our guide to offloading a diabetic foot ulcer. Depth and tissue loss are described using a grading scale, explained in the stages of a diabetic foot ulcer. Alongside offloading sit callus removal, glucose management, and treatment of infection where it is present.
Certain measures apply across all three: clearing dead tissue so the wound can close, choosing a dressing matched to how much fluid is being produced, treating infection when it appears, and attending to nutrition and the other conditions that slow repair. Where a correctly treated wound still refuses to close, advanced wound care covers the therapies used at that point.
When a leg ulcer becomes urgent
Two situations move this from an appointment to today, and they look nothing alike.
The first is infection escaping the wound. Redness traveling up the leg, fresh swelling and heat around the sore, pain climbing faster than it has been, a raised temperature, shaking chills, or simply feeling ill in a way that is hard to place. In a numb foot the whole-body signs may arrive before any local ones, so unexplained illness in someone with a foot ulcer deserves the same urgency. Where a wound sits over a bony point and has stayed open for weeks, the infection can be in the bone underneath, which is covered in signs a wound has reached the bone.
The second is a blood supply that has turned critical. Pain in the foot at rest, particularly at night and relieved by hanging the leg out of bed, a foot that goes pale, cold or dusky, toes turning blue or black, or numbness arriving together with pain. Limbs in that state are assessed the same day, since the window for restoring flow does not stay open indefinitely. The National Library of Medicine’s plain-language guide to peripheral arterial disease sets out the wider picture behind those signs.
A raised temperature alongside a leg ulcer, redness spreading up the leg, rapidly worsening pain, or a foot that suddenly changes color or temperature all need same-day medical attention.
What you can do
More than most people are told, though it depends on which type you are dealing with.
With a venous ulcer, the compression prescribed for you does its work only while it is on, so wearing it as directed is the largest single lever available to you. Walking helps, since the calf muscle acts as the pump that empties the leg. Periods with the leg raised above hip level help for the same reason, and so does moving the ankle through its full range while sitting. Keep the skin on the rest of the leg moisturized, because dry cracked skin near an ulcer becomes the next ulcer.
With an arterial ulcer, stopping smoking outranks everything else that can be done, including by the clinic. Gentle regular walking, within the limits of pain, can improve the distance you manage over months. Keep feet warm using socks and never a heat source. If raising the leg brings on pain, say so and do not push through it, since that response is information about your circulation.
With a diabetic foot ulcer, the daily foot check matters in the places you cannot easily see: between the toes, under the arch, around the heel, using a mirror or a phone camera or another person. Shoes go on with a hand swept through them first. Nothing gets worn barefoot, indoors included. An offloading boot or cast works only when it is worn for every step, which includes the trip to the bathroom at 3am, and glucose kept in the range agreed with your diabetes team supports every other part of healing.
For all three, photograph the wound once a week in the same light and from the same distance. Memory smooths change out, and a series of photographs gives whoever reviews the wound something firmer to work from than an impression. The routine side of dressing changes and monitoring sits within our chronic wound treatment service.
What to avoid
Do not buy compression stockings, wraps or tubular bandages for an ulcer nobody has assessed. On a venous leg they are the treatment; on a leg with narrowed arteries the same pressure squeezes an already inadequate blood supply, and harm from that sequence is well documented. The ankle pressure check exists precisely to prevent it.
Do not cut, file or dig at the hard skin around a foot wound, and keep medicated corn removers and acid preparations away from a numb foot entirely. Those products are designed to destroy tissue and cannot distinguish callus from the skin beneath it, and the pain that would normally stop you has already gone.
Do not apply heat to a foot that is numb or short of blood. Hot water bottles, electric blankets, radiators and hot foot soaks cause burns in feet unable to report temperature, and those burns become wounds of their own on skin that was already struggling.
Keep hydrogen peroxide, undiluted antiseptics and household disinfectants off the wound, since they damage the cells doing the repair. And do not settle into watching a leg ulcer for months with no cause established. Time spent dressing a wound whose cause has never been identified is the most common route by which these turn into long-term problems.
Living with a leg ulcer
This is the part that rarely appears in clinical summaries, and it is often what the person actually came to read.
Leg ulcers run long. Weeks at best, months commonly, sometimes longer than that, and the daily reality is bandages under clothing, shoes that no longer fit over a dressing, showers planned around keeping the leg dry, and fluid soaking through at inconvenient moments. Sleep suffers, from an aching heavy leg with a venous ulcer or from arterial pain that only eases with the foot down. Work involving standing all day becomes hard to sustain, and few people mention that to anyone until it has already cost them something.
The social side does the quieter damage. Visible bandages invite questions. Odor, when it appears, makes people cancel plans and sit apart from family, and long-standing leg ulcers are one of the conditions where patients consistently rate the effect on their life as worse than the pain. None of that is a minor complaint to be endured privately. Said plainly at an appointment it changes what gets offered, because odor control, better absorption and pain that permits sleep are all treatable targets once someone knows they matter to you.
One thing to hold onto for after it closes: healed skin over an old venous ulcer stays fragile, and the vein problem that caused it has not gone anywhere. Recurrence is common, and the compression stockings worn after healing are what hold it off. They tend to be the first thing abandoned once the wound looks better, and that decision is usually what brings people back a year later.
When to get it seen
Any open sore on the leg or foot lasting more than two weeks warrants an assessment, and the point of that assessment is to establish the cause instead of simply covering the wound.
Bring it forward if you have diabetes, since a foot ulcer in a numb foot can deteriorate quickly and quietly, and those are seen within days as a matter of routine. Bring it forward too if the pain gets worse when you raise the leg, if ankle pulses have never been checked, or if you have been treating a wound for a month with no measurable change in its size. A wound still open beyond four to six weeks despite reasonable care has earned a specialist opinion by definition.
Seek same-day care for a raised temperature or shaking chills alongside a leg ulcer, redness spreading up the leg, pain that is escalating quickly, or a foot turning cold, pale, blue or black. Those describe an infection on the move or a blood supply in trouble, and both are time-sensitive.
Common questions
Can I tell which type of leg ulcer I have myself?
You can usually reach a reasonable guess from position and pain, and that guess is worth having before an appointment. What you cannot do at home is measure the blood supply, and since the arterial reading decides whether compression is safe, the guess is a starting point and not a diagnosis.
Which type of leg ulcer is most common?
Venous, by a considerable distance. Most open sores around the ankle come from vein valves that no longer hold, which is also why the inner ankle is such a strong clue when a wound appears there.
Are diabetic and arterial ulcers the same thing?
No. A diabetic foot ulcer comes from pressure on a foot that cannot feel it, while an arterial ulcer comes from insufficient blood flow. They overlap often, because diabetes affects nerves and arteries both, and a foot with both problems is managed differently from a foot with either one alone.
Why does my leg hurt more when I raise it?
That pattern suggests the arteries are struggling to deliver blood against gravity, and it is the reverse of what a venous leg does. Report it specifically, because it can change both the tests ordered and whether compression is appropriate for you.
Can a leg ulcer have more than one cause?
Yes, and mixed ulcers are common enough that arteries get checked routinely even on legs looking plainly venous. A wound with both vein and artery problems behind it needs a plan built around the weaker circulation.
How long does a leg ulcer take to heal?
It varies widely with the cause, the size of the wound and how long it has been open. Many venous ulcers improve steadily once effective compression is in place, while arterial wounds may make little progress until blood flow is addressed. A wound showing no measurable change after a month of treatment is a reason to revisit the diagnosis.
The takeaway
Leg ulcer types divide by cause and not by appearance. Veins that leak produce a shallow, weeping, aching sore at the inner ankle on a swollen and brown-stained leg. Arteries that are narrowed produce a deeper, sharply bordered, painful wound on a toe, heel or outer ankle, on a cool foot with weak pulses, and that pain eases when the leg hangs down. Nerve damage produces a painless wound under the ball of the foot, ringed by hard skin.
The two details carrying most of the weight are position and the response to raising the leg, which will get you close, and the arterial check, which turns close into settled because it decides whether compression helps or harms. If a leg ulcer has been dressed for weeks and nobody has established which type it is, that is the question to bring to the next appointment.
Not sure which type of leg ulcer you are dealing with?
An assessment establishes the cause before the dressings are chosen, checking circulation, sensation and the state of the whole leg, and settles whether compression is safe for you.
Working out the cause of a non-healing leg or foot wound, along with the compression, offloading and circulation checks that follow from it, is handled through our chronic wound treatment service.
This article is general education and does not replace a clinical assessment. The type any particular leg ulcer belongs to can only be settled in person, with pulses, pressures and sensation checked directly, and compression should never be started or stopped on the strength of a web page. Seek same-day advice for spreading redness, a raised temperature, escalating pain, or a foot that changes color or temperature.
