Calluses and Corns

What causes calluses and corns

Skin responds to repeated pressure or rubbing by building up extra layers of keratin, the tough protein in the outer skin. This is called hyperkeratosis. It is a protective reaction, but when it becomes thick it can press on underlying tissue and hurt.

Common causes:

• Shoes that are too tight, too loose, narrow or high-heeled
• Seams or stitching inside shoes, and not wearing socks
• Toe deformities: hammer toes, claw toes and bunions create bony points that rub
• Foot shape and gait: high arches, flat feet or an abnormal walk overload certain areas
• Walking barefoot
• Hand calluses from gardening tools, weightlifting, rowing, musical instruments or manual work
• Aging: the fat pad under the foot thins, increasing pressure

Corns vs calluses vs plantar warts

Types of corns

• Hard corns: on the tops and outer sides of the toes, especially the little toe, over bony prominences
• Soft corns: between the toes, kept moist by sweat, so they are white and rubbery. Most common between the fourth and fifth toes
• Seed corns: tiny, often multiple, on the sole, sometimes linked to dry skin

Diagnosis

A doctor or podiatrist diagnoses corns and calluses by looking at them and asking about shoes, activities and symptoms. Paring the surface helps distinguish a corn's core from a wart's black dots. X-rays are sometimes taken to look at underlying bone deformities that cause pressure.

Treatment

Remove the cause

• Wear shoes with a wide, deep toe box, a low heel and soft uppers. Shop late in the day when feet are largest
• Use cushioned socks without seams
• Wear gloves for manual work and gripping sports

Home care

• Soak the area in warm water for 10 minutes to soften the skin
• Gently file with a pumice stone or foot file, removing a little at a time. Stop before the skin becomes tender or pink
• Moisturize daily with a cream containing urea or salicylic acid
• Pad the area: non-medicated, donut-shaped pads, toe sleeves, toe separators for soft corns, and cushioned insoles

Over-the-counter treatments

Medicated corn plasters and liquids contain salicylic acid, which dissolves hard skin. Follow the label carefully and protect the surrounding skin. Do not use them if you have diabetes, poor circulation, neuropathy or fragile skin, because they can cause ulcers.

Never cut corns or calluses yourself with a razor or scissors.

Professional treatment

• Paring: a podiatrist removes hard skin and the corn's core with a scalpel, usually painlessly
• Orthotics: custom insoles to redistribute pressure
• Prescription keratolytic creams
• Surgery to correct toe deformities or bony prominences when corns keep returning despite other measures

Corns and calluses with diabetes

Diabetes can reduce sensation and blood flow in the feet. A callus may hide bleeding and an ulcer underneath, and minor self-treatment can cause infection. If you have diabetes:

• check your feet every day
• see a podiatrist for any hard skin
• never use medicated corn plasters or cut skin yourself
• seek prompt care for discoloration, drainage or new pain under a callus

See diabetic foot problems for more.

Prevention

• choose well-fitting shoes, and have feet measured, as size changes with age and pregnancy
• avoid prolonged high heels and narrow toes
• use protective padding at known pressure points
• keep feet moisturized, and dry well between the toes
• treat toe deformities early

Frequently asked questions

What is the difference between a corn and a callus?

A callus is a broad, flat area of thick skin on a weight-bearing surface, usually painless. A corn is smaller and deeper, with a hard central core, and forms on or between toes. Corns press into the skin and are usually painful.

How do you get rid of corns and calluses?

Remove the pressure with better-fitting shoes and padding, soak and gently file the hard skin, and moisturize daily. Salicylic acid products can help if you do not have diabetes or circulation problems. A podiatrist can safely pare stubborn corns and fit orthotics.

Do corns have roots?

No. The hard central core of a corn is often called a root, but it is just compacted keratin pointing inward. Removing it relieves pain, but the corn returns unless the pressure causing it is removed.

Why do I get soft corns between my toes?

Soft corns form where two toe bones press together, most often between the fourth and fifth toes, and stay soft because sweat keeps the area moist. Narrow shoes are the main cause. Toe separators, wider shoes and keeping the area dry help.

Should people with diabetes treat corns at home?

No. People with diabetes, neuropathy or poor circulation should not cut corns or use medicated plasters, which can cause ulcers and infection. Daily foot checks, good shoes and regular podiatry care are recommended.