Under the Microscope: Corns

What is it?: Sometimes painful, a corn is a localized thickening of the skin that usually has a conical or circular shape. Paring down a corn one often sees a central plug or seed formed from keratin (dead skin cells). A corn may have a soft yellow ring surrounding it and a white or grayish center. Unlike calluses, which generally appear on weight-bearing surfaces, such as palms and soles, corns occur on non-weight-bearing surfaces in regions of extra pressure, such as overlying the joints of the toes.

How do you get it? While the cause of a corn is always pressure, the cause of the pressure can be different among clients. Some pressure is formed simply from ill-fitting, tight, or pointed shoes. In this case, corns often form on the outside of the small toe. However, sometimes corns form at the site of another problem, such as a bunion or hammertoe, or where rheumatoid arthritis has inflamed the joints.

How is it treated? Treatment for corns is to remove the pressure, and the pressure is most often removed by changing footwear. Often, with a change of shoes, a corn will heal on its own. Many people find relief during healing by placing a donut-shaped pad over the corn. Other protective pads, such as toe wraps and toe separators, are available at any drugstore. If there is pain at the site, a client may want to go to the doctor to have the corn pared down, which can provide immediate relief. In cases where the corn is due to the structure of the bones and joints, a doctor’s visit to diagnose and treat the underlying problem is necessary.

What can a tech do? Talk with the client about the corn, discussing her shoe choices, the level of pain, and the duration of the development. Unlike a callus, a corn doesn’t respond well to abrasive treatment; buffing a corn is likely to cause pain. Do not remove a corn even at a client’s request, especially in the case of a client with diabetes. It’s possible that the skin could be compromised while trying to remove or buff a corn, leaving the client at risk of infection. Let her know that the corn is likely to heal itself when the pressure is removed, but if she wants it to be removed immediately, she needs to schedule an appointment with her doctor.

What else? Women are more likely to develop corns than men, because women’s shoes are not always ergonomically friendly. The elderly would seem to be more likely to develop corns as age often brings arthritis; however, usually by the time arthritis is threatening, the aged have opted for better, more comfortable footwear, removing the pressure from their feet. Children generally do not get corns.

Dr. Robert S. Fawcett contributed to this article.