Corns and calluses
Corns and calluses are annoying and sometimes painful thickenings that form in the skin in areas of pressure.
Corns and calluses can be prevented by reducing or eliminating the circumstances that lead to increased pressure at specific points on the hands and feet.
Corns and calluses can be treated with many types of medicated products to chemically pare down the thickened, dead skin.
People with fragile skin or poor circulation in the feet (including many people with diabetes or peripheral arterial disease) should consult their health-care professional as soon as corns or calluses develop.
What are corns and calluses?
Corns and calluses are annoying and sometimes painful thickenings that form in the skin in areas of excessive pressure. The medical term for the thickened skin that forms corns and calluses is hyperkeratosis(plural=hyperkeratoses).
A callus refers to a more diffuse, flattened area of thick skin, while a corn is a thick, localized area that usually has a popular, conical or circular shape. Corns, also known as helomas or clavi, sometimes have a dry, waxy, or translucent appearance.
Corns and calluses occur on parts of the feet and sometimes the fingers. Corns are often painful, even when they are small. Common locations for corns are
on the bottom of the foot (sole), over the metatarsal arch (the “ball” of the foot);
on the outside of the fifth (small or “pinky”) toe, where it rubs against the shoe;
between the fourth and fifth toes.
Unlike other corns that are firm and flesh-colored, corns between the toes are often whitish and messy; they are sometimes called “soft corns” (heloma molles), in contrast to the more common “hard corns” (heloma durums) found in other locations.
What Is A Corn? What Is a Callus?
Corns and calluses can be annoying, but your body actually forms them to protect sensitive skin. Corns and calluses are often confused with one another.
Corns generally occur on the tops and sides of the toes. A hard corn is a small patch of thickened, dead skin with a packed center. A soft corn has a much thinner surface and usually occurs between the 4th and 5th toes. A seed corn is a tiny, discrete callous that can be very tender if it’s on a weight-bearing part of the foot. Seed corns tend to occur on the bottom of the feet, and some doctors believe this condition is caused by plugged sweat ducts.
Calluses can develop on hands, feet, or anywhere there is repeated friction — even on a violinist’s chin. Like corns, calluses have several variants. The common callus usually occurs when there’s been a lot of rubbing against the hands or feet. A plantar callus is found on the bottom of the foot.
What Causes Corns and Calluses?
Some corns and calluses on the feet develop from an improper walking motion, but most are caused by ill-fitting shoes. High-heeled shoes are the worst offenders. They put pressure on the toes and make women four times as likely as men to have foot problems. Other risk factors for developing a corn or callus include foot deformities and wearing shoes or sandals without socks, which leads to friction on the feet.
Rubbing or pressure can cause both soft corns and plantar calluses. If you or your child develops a callus that has no clear source of pressure, have it looked at by a doctor since it could be a wart or caused by a foreign body, like a splinter, trapped under the skin. Feet spend most of their time in a closed, moist environment — ideal for breeding bacteria. Staph infections can start when bacteria enter corns through breaks in the skin and cause the infected corn to release fluid or pus.
Corns and calluses are areas of hard, thickened skin that develop when the skin is exposed to excessive pressure or friction. They commonly occur on the feet and can cause pain and discomfort when you walk.
A corn is a small area of skin which has become thickened due to pressure on it. A corn is roughly round in shape. Corns press into the deeper layers of skin and can be painful.
Hard corns commonly occur on the top of the smaller toes or on the outer side of the little toe. These are the areas where poorly fitted shoes tend to rub most.
Soft corns sometimes form in between the toes, most commonly between the fourth and fifth toes. These are softer because the sweat between the toes keeps them moist. Soft corns can sometimes become infected.
Corns are small circles of thick skin that usually develop on the tops and sides of toes or on the sole of the foot. However, they can occur anywhere.
Corns are often caused by wearing shoes that fit poorly or certain designs that place excessive pressure on an area of the foot.
Corns often occur on bony feet as there’s a lack of natural cushioning. They can also develop as a symptom of another foot problem, such as:
a bunion – where the joint of the big toe sticks outwards as the big toe begins to point towards the other toes on the same foot
hammer toe – where the toe is bent at the middle joint
Calluses are hard, rough areas of skin that are often yellowish in colour. They can develop on your foot, most often around the heel area or on the skin under the ball of the foot.
They can also develop on the palms of the hands and knuckles.
Calluses are larger than corns and do not have such a well-defined edge. As callused skin is thick, it is often less sensitive to touch than the surrounding skin.
Calluses develop when the skin rubs against something, such as a bone, a shoe or the ground. They often form over the ball of your foot because this area takes most of your weight when you walk. This is particularly the case when high heels are worn regularly.
Excessive pressure on bony areas of the foot, badly fitting shoes, dry skin and reduced fatty padding are all possible causes of calluses.
A callus is larger and broader than a corn and has a less well-defined edge. These tend to form on the underside of your foot (the sole). They commonly form over the bony area just underneath your toes. This area takes much of your weight when you walk. They are usually painless but can become painful.
Treating corns and calluses
Corns on feet will not get better unless the cause of the pressure is removed. If the cause is not removed, the skin could become thicker and more painful over time.
A corn is a symptom of an underlying problem. You should only treat it yourself when you know what has caused it and after you have spoken to a specialist about the best way to manage it.
Over-the-counter treatments for corns, such as corn plasters, are available from pharmacists. However, they do not treat the cause of the corn and may affect the normal, thinner skin surrounding the corn.
Corn plasters may not be suitable for certain people, such as those with diabetes, circulation problems or fragile skin.
As with corns, you should only treat calluses yourself after a podiatrist has identified the cause and advised you about treatment.
The podiatrist may be able to treat corns or badly callused areas using a sharp blade to remove the thickened area of skin. This is painless and should help reduce pain and discomfort. They can also provide advice on self-care and prescribe special insoles.
You can also help prevent corns and calluses by looking after your feet and choosing the right shoes to wear.
A corn, clavus (plural: clavi) is a specially-shaped callus of dead skin. It usually forms on hairless and smooth (glabrous) skin surfaces, especially between the toes or fingers.
Corns and calluses generally form when the skin tries to protect an underlying area from injury, pressure or rubbing. They are not usually painful, but can become sore if they grow.
Corns and calluses affect women more commonly than men, as well as people who wear ill-fitting shoes, individuals with sweaty feet, and those who have to stay standing for long periods each day. Corns and calluses are also more common among people with foot problems, such as hammer toes or bunions.
A corn will most typically develop on the top and side of the toes – its inside may be either soft or hard. Hard corns are common; they tend to be small and occur in areas of firm, hard skin – areas of thickened skin or calluses. Bony areas of the foot are favorite sites for hard corns. Soft corns tend to be whitish in color, and have a rubbery texture – they more commonly occur between the toes (areas of moist and sweaty skin).
Calluses are yellowish or pale in color; they feel lumpy to the touch. However, as the skin is thick it may be less sensitive to touch compared to the skin around it. Calluses are often bigger and wider than corns, and do not have such defined margins (edges). Calluses commonly appear where the skin frequently rubs against something, such as a bone, some item of footwear, or the ground. They typically form over the bony area just under the toes – areas of skin which take the person’s weight when they are walking.
Although complications are uncommon, people with diabetes or other conditions which affect circulation to their feet are more susceptible.
What are the signs and symptoms of corns and calluses?
A symptom is something the patient feels and reports, while a sign is something other people, such as the doctor detect. For example, pain may be a symptom while a rash may be a sign.
Patients often say they feel as if they are walking on stones. The following signs or symptoms may indicate the presence of corns or calluses:
A raised bump which is hardened
A thick and rough area of skin
Flaky and dry skin
Flaky and waxy skin
Pain under the skin
Tenderness under the skin
People sometimes mistakenly use the terms corns and calluses interchangeably – but they are not the same:
Corns versus calluses
Corns are smaller than calluses
Corns generally (not always) have a hard center
Corns have a hard center surrounded by inflamed skin
Corns usually occur in non-weight bearing parts of skin (not always)
Corns can be painful when pressed
Calluses are not generally painful
Calluses are usually larger than corns, and vary in shape
Calluses generally develop on the soles of the feet, especially under the heels or balls, on the palms of the hands, and also on the knees.
If a corn or callus becomes very inflamed or painful the sufferer should seek medical advice. Patients with poor circulation, such as those with diabetes, should talk to their doctors before self treating corns and calluses.
Why do corns and calluses develop?
Hyperkeratosis simply means thickening of the skin. This thickening occurs as a natural defense mechanism that strengthens the skin in areas of friction or excessive pressure. Abnormal anatomy of the feet, such as hammer toe or other toe deformities, can lead to corn or callus formation as can bony prominences in the feet. Footwear that is too short or too tight or that exerts friction at specific points can also cause skin thickening that leads to corns and calluses. Abnormalities in gait or movement that result in increased pressure to specific areas can also be the cause.
It can be hard to know why finger corns develop since they often don’t appear at sites of obvious pressure. Finger calluses may develop in response to using tools, playing musical instruments such as the guitar, or using work equipment that exerts pressure at specific sites.
What are risk factors for corns and calluses?
As mentioned above, any condition or activity that results in increased friction over the fingers or toes can lead to the development of corns or calluses. People of all ages can be affected but they are particularly common in people over 65 years of age. Corns and calluses have been shown to affect 20%-65% of people in this age range. Some of these risk factors are abnormalities in anatomy of the feet or toes; abnormalities in gait; bunions; poorly fitting footwear; using equipment, tools, or instruments that exert pressure on specific locations on the fingers; certain occupations, such as farmers or garden workers.
What are symptoms and signs of corns and calluses?
Corns and calluses are hardened, thick areas of skin. The area may be dry and may appear to be scaly or flaky. Corns can cause pain or discomfort if they interfere with walking or other activity. Calluses are typically painless.
How are corns and calluses diagnosed?
The diagnosis can be made by observing the characteristic changes in the skin. Specialized tests are not necessary.
How can corns and calluses be treated?
Corns and calluses can be treated with many types of medicated products to chemically pare down the thickened, dead skin. These products all share the same active ingredient — salicylic acid, the ingredient used in over-the-counter wart-removal products.
Salicylic acid is a keratolytic, which means it dissolves the protein (keratin) that makes up most of both the corn and the thick layer of dead skin which often tops it. Used as indicated on the package directions, these products are gentle and safe for most people. Salicylic-acid treatments are available in different forms including applicators, drops, pads, plasters.
All of these treatments will turn the top of the skin white and allow the dead tissue to be trimmed or peeled away, making the corn protrude and hurt less.
It generally is recommended that salicylic acid not be used by people with diabetes or when there is frail skin or poor circulation (because of concern about how the skin can heal). In these situations, application of salicylic acid can potentially lead to ulcer formation on the skin. A health-care professional can help determine whether salicylic acid-based products are safe for use on a particular individual.
Do not attempt to cut or shave away corns and calluses at home. This can lead to potentially dangerous infection of the surrounding tissues. This should be performed by a podiatrist or other health-care professional.
A health-care professional may also prescribe antibiotics for any corns or calluses that have become infected.
When should someone seek professional treatment for corns or calluses?
If the corn is bothersome and doesn’t respond to salicylic acid and trimming, consider seeing a physician or podiatrist who can physically pare corns with scalpels. Podiatrists also can measure and fit people with orthotic devices to redistribute their weight on their feet while they walk so that pressure from the foot bones doesn’t focus on their corns. (Off-the-shelf cushioned insoles are one size fits all and may not be effective.)
People with fragile skin or poor circulation in the feet (including many people with diabetes or peripheral arterial disease) should consult their health-care professional as soon as corns or calluses develop. Further, someone should seek medical care immediately if corns or calluses show signs of infection (such as increasing pain, the presence of pus or other drainage, swelling, and redness).
Surgical removal of corns is rarely necessary. When a corn is surgically removed, the pressure that caused it to form in the first place will just make it come back if this pressure is not removed or reduced. When necessary, surgery for corns involves shaving the underlying bone or correcting any deformity that is causing undue pressure or friction on the skin.
What is the prognosis for corns and calluses?
Corns and calluses are not serious conditions and can be managed with home-care remedies or medical treatment. Surgery is very rarely necessary. However, even with management, corns and calluses may recur if there is continued pressure or friction on the affected area.
How can corns and calluses be prevented?
In many situations, calluses and corns can be prevented by reducing or eliminating the circumstances that lead to increased pressure at specific points on the hands and feet. Potential preventive measures therefore include the following:
Wearing well-fitting comfortable shoes is useful. The idea is to avoid having footgear press on the outside of the fifth toe or pressing the fourth and fifth toes together to prevent corns in these areas; another approach is to pad the potentially affected area. Many sorts of padding are available at the drugstore:
Cushions to put between the toes.
Foam or moleskin pads to put over the places where corns form
Foam pads with holes in the center (like donuts or bagels), which redistribute pressure around the corn instead of right over it
Cushioned insoles to pad the feet and alleviate mechanical pressure
What are the risk factors for corns and calluses?
A risk factor is something which increases the likelihood of developing a condition or disease. For example, obesity significantly raises the risk of developing diabetes type 2. Therefore, obesity is a risk factor for diabetes type 2. The following risk factors are linked to a higher incidence of corns and calluses:
Bunions, hammertoe and other foot problems and deformities – a bunion is an abnormal, bony bump that develops on the joint at the base of the big toe. A hammertoe is when a toe becomes curled up like a claw.
Excessive hand friction – people who use hand tools without wearing gloves have a higher risk of developing calluses.
Old age – elderly people have less fatty tissue in their skin, which can result in less padding and a higher risk of developing calluses, especially on the ball of their foot.
What are the causes of corns and calluses?
Anything that results in higher levels of pressure or friction on the skin can cause corns or calluses to develop.
Badly fitting shoes – the shoes may be too tight (pressure), or sometimes too loose (rubbing/friction). Very high heels. A badly placed seam in a shoe can rub against the skin.
Socks – either not wearing any socks or having socks that don’t fit properly.
Hand tools – some work, house or garden tools, if used repetitively, can cause calluses in the person’s hands.
Walking barefoot – if done regularly, the skin will thicken to protect itself.
Repeated actions on the feet (or one foot) – jogging or walking in an odd way.
Diagnosis of corns and calluses
The GP (general practitioner, primary care physician) will interview the patient and ask about his/her lifestyle. The patient’s footwear may also be checked. There will be a physical examination.
If the doctor suspects there may be an underlying bone structure problem the patient may be referred for an X-ray.
What are the treatment options for corns and calluses?
If the corns and calluses have been caused by repetitive actions, avoiding them will most probably solve the problem. Wearing shoes and socks that fit properly, as well as having protective pads and other self-care measure also help.
If the corn or callus does not go away, or continues to be painful regardless, the following therapies may help:
Creams – special creams may be recommended to rehydrate areas with extra thick skin.
Trimming or removing – the doctor pares down the thickened skin, or uses a scalper to trim a large corn. A podiatrist (foot doctor) may remove some of the hard skin that surrounds the corn so that the center of it can be removed.
Salicylic acid – after trimming the doctor may apply a patch with 40% salicylic acid. The patient will need to replace the patch periodically. A pumice stone or metal nail file is usually used to rub away dead skin before applying a new patch.
Foam wedges – these may be used for corns on the toes to reduce pressure. Sometimes special silicone wedges may be used.
Antibiotics – an antibiotic ointment may be prescribed to lessen the risk of infection.
Orthotics – these are custom-made padded shoe inserts which may help people with an underlying foot deformity.
Bone problem surgery – the bone may need to be surgically aligned (rare).
How to prevent corns and calluses?
The following measures may help reduce the risk of developing corns and calluses:
Wash your feet with soap and water every evening. Use a scrubbing brush.
Apply a specially moisturizing foot cream after washing and drying them well. Do not use a body lotion.
Make sure your shoes and socks are well-fitting, and with seams that do not rub the skin.
Buy your shoes later on during the day – i.e. when trying on new shoes do so when your feet are at their largest (feet swell slightly as the day progresses).
Any foot pain or skin irritation in the foot should not be ignored.
Regularly see a foot specialist for a foot checkup.
When trimming your toenails, cut straight across, and not down at angles or over the edges.
Use a pumice stone or foot file regularly. Make sure you remove hard skin gently.
Change your socks every day. Do not let your feet become sweaty.
Protect your hands – when using tools, either wear padded gloves or pad the tool handles.
What causes corns and calluses?
The small bones of the toes and feet are broader and lumpier near to the small joints of the toes. If there is extra rubbing (friction) or pressure on the skin overlying a small rough area of bone, this will cause the skin to thicken. This may lead to corns or calluses forming.
The common causes of rubbing and pressure are tight or poorly fitting shoes which tend to cause corns on the top of the toes and side of the little toe. Also, too much walking or running which tends to cause calluses on the sole of the feet. Corns and calluses are more likely to develop if you have very prominent bony toes, thin skin, or any deformities of the toes or feet which cause the skin to rub more easily inside shoes.
What are the treatments for corns and calluses?
If you develop a painful corn or callus it is best to get expert advice from a person qualified to diagnose and treat foot disorders (a podiatrist – previously called a chiropodist). You should not cut corns yourself, especially if you are elderly or have diabetes.
Advice and treatments usually considered include the following:
Trimming (paring down)
The thickened skin of a corn or callus can be pared down by a podiatrist by using a scalpel blade. The pain is usually much reduced as the corn or callus is pared down and the pressure on the underlying tissues eased. Sometimes, repeated or regular trimming sessions are needed. Once a corn or callus has been pared down, it may not return if you use good footwear.
If the skin seems to be thickening up again, a recurrence may be prevented by rubbing down the thickening skin with a pumice stone or emery paper once a week. Many people can do this themselves. It is best to soak your foot in warm water for 20 minutes to soften the thick skin before using a pumice stone or emery paper. A moisturising cream used regularly on a trimmed corn or callus will keep the skin softened and easier to rub down.
There are different types of medicated products which work by chemically paring down the thickened, dead skin on corns and calluses. These usually contain salicylic acid, which is also present in many wart-removal products.
Salicylic acid is a keratolytic, which means it dissolves the protein (keratin) that makes up most of both the corn and the thick layer of dead skin which usually tops it. It is important to use these products as directed in the package directions; these products are gentle and safe for most people. Salicylic acid treatments are available in different forms including drops, pads and plasters.
All these treatments will turn the top of your skin white and then you will be able trim or peel away the dead tissue. This results in the corn sticking out less, which will make it less painful.
Although these products can work well, they should not be used if you have diabetes or have poor circulation. This is because your skin is less likely to heal well after using salicyclic acid and there is a risk that an ulcer may develop.
Shoes and footwear
Tight or poorly fitting shoes are thought to be the main cause of most corns and calluses. Sometimes a rough seam or stitching in a shoe may rub enough to cause a corn. The aim is to wear shoes that reduce pressure and rubbing on the toes and forefeet. Shoes should have plenty of room for the toes; have soft uppers and low heels. In addition, extra width is needed if corns develop on the outer side of the little toe. Extra height is needed if corns develop on the top of abnormal toes such as ‘hammer’ or ‘claw’ toes.
Correcting poor footwear will reduce any rubbing or friction on your skin. In many cases, a corn or callus will go away if rubbing or pressure is stopped with improved footwear. If you have had a corn or callus pared away, a recurrence will usually be prevented by wearing good footwear. If you are able, going barefoot when not outdoors will also help.
Some people with abnormalities of their feet or toes will need special shoes to prevent rubbing. A podiatrist can advise you about this.
Footpads and toe protection
Depending on the site of a corn or callus, a cushioning pad or shoe insole may be of benefit. For example, for a callus under the foot, a soft shoe inlay may cushion the skin and help the callus to heal. If there is a corn between your toes, a special sleeve worn around your toe may ease the pressure. A special toe splint may also help to keep your toes apart to allow a corn between toes to heal. A podiatrist will be able to advise you on any appropriate padding, insoles or appliances you may need.
If you have a foot or toe abnormality causing recurring problems, an operation may be advised if all else fails. For example, an operation may be needed to straighten a deformed toe, or to cut out a part of a bone that is sticking out from a toe and is causing problems. If you need an operation then you will be referred to a surgeon who will be able to discuss this with you in more detail.
Occasionally corns or calluses can become infected. If this happens then your skin around the corn (or callus) will become red and sore. Your doctor will be able to prescribe medicines called antibiotics if this happens.