A corn, also known as a clavus, is a thickening of the skin that usually develops on the foot due to repeated friction and pressure. Corns can be extremely painful and can lead to more serious health problems like infections and serious complications for people with diabetes if left untreated.
Anyone can get a corn on the foot, but people who wear ill-fitting shoes regularly are more likely to develop these painful skin lesions.
What is a corn on the foot?
A corn is similar to a callus. Both involve hardened layers of skin that develop in response to friction, which is known as hyperkeratosis. Corns generally occur on parts of the feet that don’t bear weight, like the tops and sides of your toes, and they can be very painful. Calluses, meanwhile, usually occur on the soles of the feet and are rarely painful.
Corns are the body’s response to repeated friction and rubbing on the foot. Your body develops corns to protect sensitive areas. Corns usually emerge on a joint of the foot, like on the toe. They can also develop on other bony parts of the feet. Sometimes they appear on the bottom of the foot, though this is rare.
Corns on the foot often look like a small raised lump with a dry, circular patch of skin surrounding it. Under this lump is a central core that is tender and located over the area of the greatest pressure on the foot.
Corns are most often found on athletes, people with gait abnormalities or foot deformities, and people who wear tight-fitting shoes.
The treatment of corns on the feet varies from case to case. Corns can be small, or they can become large, painful, and infected. You can unconsciously adjust the way you walk to accommodate the pain of a corn. If left untreated, this can affect your posture and bone alignment, among other things, causing long-term problems.
Signs and symptoms of a corn
Corns are a common foot problem. You can identify a corn on the foot by:
- A hard bump on the skin surrounded by a dry patch of skin
- A tender, raised lump on the skin that’s painful when pressure is applied
A key difference between corns and calluses is that calluses are rarely painful. Corns have a central core. A pressure point — the sensitive area the corn is protecting — is located under the central core. That’s what makes a corn so painful.
Types of corns
There are two main types of corns:
Hard corns usually form on the top or the side of the foot. It’s common to get them in a place where there is constant or repetitive friction from a tight-fitting shoe.
Soft corns commonly develop between joints, like the area between the toes. They’re especially common in people who wear shoes that cause friction between the toes, like high heels. They are soft due to the level of skin moisture where they form.
Causes of corns on the foot
Corns are your body’s response to repeated pressure on a sensitive area. The following groups of people are most likely to develop corns on the foot:
When to see the doctor for corns
A corn can impact you by causing extreme pain when you walk. This can greatly affect your quality of life. Some corns can be small and unproblematic, while others can be extremely painful and become infected.
Diagnosing corns on the foot
Podiatrists are doctors who diagnose and treat foot problems. If your corn becomes painful, it’s necessary to seek treatment to avoid any secondary issues.
Treatments for corns
Treating corns properly when they become painful is important. Untreated corns can lead to:
- Infection. Infected corns can cause multiple issues. In rare cases, bacteria from the infected site can spread to the joints (septic arthritis) or nearby bone tissue (osteomyelitis).
- Changes in posture and bodily alignment. When you experience severe pain, you can often subconsciously change your posture or pressure distribution to avoid stepping on the painful area. This can disrupt your natural posture and cause problems with your alignment that may affect your back and knees.
- Complications in people with diabetes. People with diabetes can suffer from complications of nerve damage in the hands and feet. They may not be able to feel things like small cuts on the feet or corns, which can result in corns being left untreated, leading to issues like posture imbalance, infection, and even death of the tissue surrounding the corn (gangrene).
You can treat a painful corn by relieving the pressure around the bump itself. There are over-the-counter remedies for corns. These include moleskin patches or padded plasters placed around the corn to relieve pressure.
These plasters often contain salicylic acid, a topical acid meant to slowly burn off the thick skin of the corn. Most doctors discourage the use of these at-home remedies because salicylic acid can affect the healthy tissue surrounding the corn and cause complications in patients with reduced circulation.
Doctors can also shave or pare down a corn using a scalpel blade. This is meant to relieve pressure and reduce pain. After paring down the corn, they may recommend using a pumice stone to file your skin in order to maintain the new, thinner skin. Moisturizer is also important to keep the skin soft.
A podiatrist may prescribe special insoles or shoes to accommodate a corn that causes a foot deformity. Rarely, a doctor might recommend surgery if a foot deformity is the underlying cause of the corn.
Health Solutions From Our Sponsors
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HealthMark: "An Untreated Foot Corn Can Cause Blisters, Arthritis, Or Worse."
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Medlife: "Impact of Corns & Calluses on Diabetics and How to Treat Them."
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Patient: "Corns and Calluses."