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  • Definition

    A callus is a thickened pad of skin, usually on the weight-bearing portion of the sole, that results from chafing and pressure.

    A corn is a highly concentrated callus that occurs at a pressure point, such as the top of the toe or under a toe joint.

    Either can be painful when they press on sensitive nerves in the surrounding skin, which may become red and inflamed.


    Corns are small, rough mounds of firm, dead skin that form on or between the toes. Their hard, waxy core, which bores down into the skin and press on the underlying tissue and nerves, can cause extreme pain.

    Corns are sometimes associated with bursae (fluid-filled sacs that cushion the juncture of two or more bones), which can become irritated, resulting in bursitis.

    Corns are caused by a great deal of pressure or friction on the toes, usually from ill-fitting shoes or high heels. Since the skin acts as the body's protector, corns form when the body attempts to protect the troubled area from more pressure by building up a mass of dead skin cells and secreting a hard substance called keratin. Persons who have abnormal bone structure in their feet or certain types of arthritis, tend to develop corns. Generally, those who avoid high-heeled or tight-fitting shoes should be able to avoid corns.


    Corns are usually regular in shape and can be white, gray, or yellow. They most often form on the outside of the first or fifth toes, since this is the point that pressure most often occurs. Corns that form between the toes are called soft corns, and they are not as firm as other corns because of moistness between the toes.


    Severe or persistent corns must be treated by a doctor, however, they rarely require surgery.

    Persons with diabetes, atherosclerosis or other circulatory diseases should never treat a corn themselves, as their risk of infection is much greater.

    Many acid preparations are available for reducing corns and calluses. A commonly used prescription preparation is a mixture of salicylic acid, lactic acids and collodion (Duofilm, Salactic Film and Viranol).

    The over-the-counter acids are weaker than their prescription counterparts, such as trichloroacetic acid, 80 percent (Tri-Chlor). Such preparations may be more harmful than helpful, because the bony prominences of the toes have such thin coverings. Acids should not be used by diabetic patients and are not advisable for individuals with impaired sensation or for the elderly with thin skin.


    What is the best treatment for corns?

    How long does it take to eliminate a corn?

    Is there anything that can be done to the skin before applying any of the acid preparations?

    How much and how often should the preparation be applied?

    Are soaking and filing the area good methods of corn removal?

    Will better fitting shoes or the elimination of the source of pressure allow the corns to disappear on their own?

    If surgery is recommended, can the procedure be done under a local anesthetic? What are the risks?

    Corns are best treated by first eliminating the cause of the pressure. Over-the-counter preparations are available. These include padding (to reduce the friction on the area), ointments and medicated pads (to soften and blister the skin layers, making them easier to remove and reducing the pain).

    Wear comfortable shoes. Ill-fitting footwear often causes corns and calluses. Wear shoes that do not cramp your toes.

    Adjust your walking style. An improper gait, such as walking on the sides of your feet, can produce calluses and corns.

    Look at the heels on an old pair of shoes. If one side is markedly worn, you may be shifting your weight unevenly as you walk. Ask your physician or podiatrist if a shoe insert (orthotic) could help distribute your weight more evenly.

    Protect your skin. Visit your pharmacy or medical supply store. You may select from a wide variety of readily available over-the-counter products such as tufts of lamb's wool, moleskin pads and toe coverings (to protect your skin).