A callus is an abnormal thickening of the top layer of skin, which is composed of the natural protein, keratin. Calluses can form on areas that are repeatedly exposed to friction or pressure. They are usually painless or only mildly painful.
A corn is a small, well-defined, thickened area of skin that forms on the toes. Corns put pressure on the underlying skin against the bone. They are usually inflamed and painful.
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Calluses and corns form as protective pads of skin in response to repeated friction or pressure. Causes include:
Factors that may increase the risk of calluses and corns include:
Symptoms of calluses include:
Symptoms of corns include:
The skin where a corn or callus has formed will be examined. Diagnosis is based on symptoms and visual observation of the corn or callus. They are easily distinguished by:
A scalpel may be used to remove layers of the skin to make sure that it is a corn or callus, rather than a wart.
Treatment of calluses and corns usually include self-care and medication. In severe cases, minor surgery may be necessary. People with diabetes or circulatory problems should always see a doctor or podiatrist for treatment. Self-treatment may lead to severe infection in these individuals.
Applying keratin-dissolving medication (such as salicylic acid) can help dissolve calluses and corns more quickly. Apply medication carefully, since it contains acid that may damage nearby healthy skin.
In severe cases, calluses and corns may need to be shaved off with a scalpel. More extensive surgery may be needed to correct foot deformities that cause extremely painful or debilitating corns.
To prevent calluses:
To prevent corns:
American Orthopaedic Foot and Ankle Society
Family Doctor—American Academy of Family Physicians
Canadian Orthopaedic Association
Canadian Orthopaedic Foundation
Callus. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated January 19, 2011. Accessed February 15, 2016.
Corn. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated June 10, 2010. Accessed February 15, 2016.
Corns. Ortho Info—American Academy of Orthopaedic Surgeons website. Available at: . Updated September 2012. Accessed February 15, 2016.
Last reviewed March 2016 by Michael Woods, MD Last Updated: 1/13/2014