A corn or callus is an area of hard, thickened skin on the foot that is formed in response to pressure or friction. They are part of the body’s defence system to protect the underlying tissues. If the cause of pressure is not relieved, calluses can become painful. If pressure becomes concentrated in a small area, a ‘hard’ corn may develop. A corn has a central core.
Common sites of corn and callus formation are the ball of the foot, under the big toe, the tips and the tops of toes. ‘Soft’ corns may develop between the toes, where the skin is moist from sweat or inadequate drying. Sometimes, the pressure of the corn or callus may produce inflammation, which can result in acute pain, swelling and redness.
Corns and calluses may be a sign that you have an underlying foot disorder, such as a joint that is out of alignment. This is why it is important to seek professional advice rather than attempt to treat calluses or corns yourself.
The symptoms of corns and calluses can include:
- Thickened patch of hard skin on the foot.
- Hard, small bump of skin that may have a central core.
- White and rubbery bumps of skin (‘soft’ corns, in between the toes).
- In some cases, the callus pushes into the foot, rather than spreading across the skin surface.
- Pain when pressure or friction is applied to the area.
Some people are at higher risk
Anyone can develop corns or calluses, but some groups are particularly at risk, including:
- Elderly people – because ageing skin loses elasticity and fatty tissue.
- People who spend a lot of time standing up – because of the continuous weight-bearing pressure on their feet.
- People with feet that roll inwards (flat feet) – flat feet place excessive pressure on the ball of the foot beneath the big toe, and the inside of the heel.
- A person with foot complaints (such as a hammer toe, bunions or arthritis) – because a bony prominence can rub against the shoe or neighbouring toes.
- People who regularly wear shoes that are narrow, tight, ill-fitting or high-heeled.
Don’t try to treat corns and calluses yourself
Over-the-counter treatments, such as corn plasters, don’t treat the underlying foot disorder. The body protects skin tissues from pressure or friction damage by producing an area of hard skin so, unless the cause of the pressure or friction is found and removed, calluses and corns will continue to form. These over-the-counter treatments can also damage the healthy surrounding skin, if used incorrectly. Don’t ever attempt to cut away or scrape a callus. If you accidentally cut yourself the humid environment of socks and shoes makes infection of the wound more likely.
Seek advice from your podiatrist
If you have corns or calluses, or think you may be developing them, see your podiatrist for treatment. Options may include:
- Investigation and treatment of the possible causes – for example, treatment for bunions.
- Professional reduction of the callus or corn to relieve pain.
- Customised arch supports or padding on various areas of the foot to temporarily redistribute pressure, for example, you may need to wear little foam wedges between your toes.
- If needed, permanent inserts to wear inside your shoes (orthoses) to offer long term pressure relief.
- Advice on appropriate footwear and foot care.