A corn is a type of callus.
They happen when the skin tries to protect an underlying area from injury, pressure, or rubbing.
Neither is dangerous, but they can cause irritation.
They are more common among people who wear ill-fitting shoes, have sweaty feet, and those who stand for long periods each day.
They affect women more than men.
Contents of this article:
Here are some facts about corns and calluses. There is more detailed information in the main article,
- Corns have a distinct, often hard, center, which may be surrounded by inflamed skin.
- Corns can be painful when pressed, but calluses are not usually painful.
- Calluses are usually larger than corns, and they vary in shape, while corns tend to be smaller, round and well-defined.
- Calluses normally develop on the soles of the feet, especially under the heels or balls, on the palms of the hands, and also on the knees. Corns often occur in non-weight-bearing parts of the skin.
- A pumice stone or over-the-counter topical medicine can be used to treat corns and calluses without going to see a doctor.
- Painful corns or calluses may need medical attention.
- Lifestyle and clothing changes can help prevent corns and calluses.
What is the difference between corns and calluses?
People sometimes mistakenly use the terms corns and calluses interchangeably, but they are not the same.
What is a callus?
A callus is a section of skin that has become toughened and thick because of friction, pressure, or irritation. They often happen on the feet, but they can occur on the hands, elbows, or knees.
Calluses are yellowish or pale in color. They feel lumpy to the touch, but, as the skin is thick, it may be less sensitive to touch compared with the skin around it.
Calluses are often bigger and wider than corns, with less defined edges. They 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 that take the person's weight when they are walking.
What is a corn?
A corn is a kind of callus, made of dead skin.
They usually form on smooth, hairless skin surfaces, especially on the top or the side of the toes. They are usually small and circular, with a clearly defined center that can be hard of soft.
Hard corns tend to be small, and they occur in areas of firm, hard skin, where the skin has thickened or where there are calluses, and in bony areas of the foot.
Soft corns tend to be whitish in color, with a rubbery texture. They more commonly occur between the toes, in areas of moist and sweaty skin.
Calluses and corns are not normally harmful, but sometimes they may lead to infections or ulcerations of the skin, especially among people with diabetes and those with poor circulation in the feet.
Signs and symptoms
Calluses have become toughened and thick due to friction. People can normally carry out treatment at home using over-the-counter products, but in especially painful cases may wish to see a podiatrist.
Corns and calluses can make a person feel as if they are walking on stones.
The following signs or symptoms may indicate that there is a corn or callus:
- a raised, hardened bump
- a thick and rough area of skin
- skin that is flaky and dry or flaky and waxy
- pain or tenderness under the skin
If a corn or callus becomes very inflamed or painful, the patient should seek medical advice.
Patients with poor circulation, fragile skin, or nerve problems and numbness in the feet should talk to their doctors before treating corns and calluses at home.
Causes and risk factors
The following risk factors are linked to a higher incidence of corns and calluses:
- anything that causes pressure or friction on the skin
- shoes that are too tight or too high-heeled, causing pressure
- shoes that are too loose, causing friction
- a badly placed seam in a shoe that rubs against the skin
- socks that do not fit well
- wearing no socks
- walking barefoot regularly, as the skin will thicken to protect itself
- repeated actions such as jogging or walking in a particular way
- older age, as there is less fatty tissue in the skin, which means less padding and a higher risk of developing calluses, especially on the ball of the foot
Calluses often appear on the feet, but friction and pressure can also cause calluses on the hands.
People who frequently cycle or use hand tools without wearing gloves can develop them. Repeated kneeling or resting elbows on a table can cause calluses on the knees or elbows.
Bunions, hammertoe, and other foot problems and deformities increase the risk of corns and calluses. 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.
People can treat corns and calluses at home with a pumice stone or salicylic acid.
Many people treat corns and calluses at home, using over-the-counter products from a pharmacy.
- Soaking the corn or callus in warm water for 5 to 10 minutes, then filing or scraping the area with a pumice stone. Circular or sideways motions help remove dead skin.
- Using moisturizer every day on the feet. Products that contain salicylic acid, urea, or ammonium lactate help soften the dry skin to prepare it for filing.
- If repetitive actions are causing the corns and calluses, avoiding these actions can often solve the problem.
- Shoes and socks that fit properly, protective pads or insoles, and other self-care measure can help. Foam or silicone wedges may be used between the toes to reduce pressure on a corn. Orthotics are custom-made padded shoe inserts which may help people with an underlying foot deformity.
When to see a doctor
If the corn or callus is very painful, or if the person has diabetes, fragile skin, or circulatory problems, it is best to consult a doctor or a podiatrist, who is specialized in foot care.
The doctor will examine the feet, ask the person about their lifestyle, and they may check their footwear.
A podiatrist, or foot doctor, may remove some of the hard skin that surrounds the corn so that the center of it can be removed.
After trimming the skin, the doctor may apply a patch with 40 percent 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.
If there is infection or a risk of infection, the doctor may prescribe antibiotic ointment. Red and swollen skin around the corn or callus can indicate an infection.
If the doctor suspects there may be an underlying bone structure problem, they may refer the patient for an x-ray, and possibly surgery.
What is salicylic acid?
The standard treatment for corns and calluses is salicylic acid, which is also used in wart treatment.
This is a keratolytic, which means it dissolves the protein, or keratin, that makes up the corn and the dead skin around it.
It is available in creams, pads, and plasters, or it can be applied using an applicator or a dropper.
The top of the skin will turn white, and the dead tissue can be cut or filed away.
Once the corn or callus has gone, the individual can soak and rub down the area with a pumice stone each week, if the hard skin shows signs of from coming back.
Salicylic acid comes in different concentrations. Stronger doses may work faster, but it will need a prescription.
The ingredients can irritate surrounding skin, so care should be taken when applying it. Do not use this on a cracked corn or callus.
When treating corns and calluses at home, it is important not to remove too much skin, as this can lead to pain and infection.
Older people and those with diabetes should not scrape, file, or trim their feet at home, as this can lead to infections that are difficult to cure. It could lead to ulcers on the skin.
They should ask a doctor before using salicylic acid, as this, too, can cause ulcers.
Any cutting or paring of skin is best done by a podiatrist or other health professional.
Repeated or regular trimming may be needed, as the corn or callus may recur.
The following measures may help reduce the risk of developing corns and calluses:
Wearing well-fitting socks and footwear can help to prevents corns and calluses.
- Wash the 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.
- Wear well-fitting shoes and socks with seams that do not rub the skin.
- Shop for shoes later in the day, when the feet are at their largest, because feet swell slightly as the day progresses.
- Deal with any foot pain or skin irritation as it arises.
- Have a regular check up with a foot specialist.
- When trimming the toenails, cut straight across, and not down at angles or over the edges.
- Use a pumice stone or foot file regularly, and remove hard skin gently.
- Wear clean socks every day and use talcum powder to prevent sweating.
- Protect the hands when using tools, either with padded gloves or by padding the tool handles.
With treatment, corns and calluses can be removed, but they may return without lifestyle or footwear changes.