What are calluses and corns?

Calluses and corns are areas of thick, hardened, dead skin. They form to protect the skin and structures under the skin from pressure, friction, and injury. They may appear grayish or yellowish, be less sensitive to the touch than surrounding skin, and feel bumpy. Calluses on the hands and feet of an active person are normal. Calluses and corns become a problem when they grow large enough to cause pain.

• Calluses generally form on the hands or feet, although they may form wherever there is pressure on the skin, such as on the knees or elbows.
  • Calluses on the hands generally form at the base of the fingers. They usually are not painful and may be useful. For example, a carpenter might develop calluses that protect his or her hands from scrapes and cuts while working. A tennis player might develop calluses on the palm that protect his or her hand from the pressure and friction of handling a tennis racket.
  • Calluses on the feet generally form on the ball of the foot, the heel, and the underside of the big toe. They often form where the foot and the beginning of the toe meet (under the end of the metatarsal bone).
• Corns generally are found where toes rub together. Corns have an inner core that can be soft or hard. A soft corn is found between toes (usually the fourth and fifth toes), while a hard corn is often found over a bony part of a toe (usually the fifth toe).

See pictures of calluses and hard and soft corns.

What causes calluses and corns?

Calluses and corns are caused over a period of time by repeated pressure or friction on an area of skin. The pressure causes the skin to die and form a hard, protective surface. A soft corn is formed in the same way, except that when perspiration is trapped where the corn develops, the hard core softens. This generally occurs between toes. Calluses and corns are not caused by a virus and are not contagious.

Repeated handling of an object that puts pressure on the hand, such as tools (gardening hoe or hammer) or sports equipment (tennis racket), typically causes calluses on the hands.

Calluses and corns on the feet are often caused by pressure from footwear.

• Tight shoes squeeze the foot.
• High-heeled shoes squeeze the front part of the foot.
• Loose shoes may cause your foot to slide and rub against the shoe.
• Shoes with a thin sole can create more pressure on the ball of the foot when walking than do thicker-soled shoes.
• Wearing sandals and shoes without socks can lead to increased friction.
• The foot may rub against a seam or stitch inside the shoe.
• Socks that don't fit may result in pressure where a sock bunches up.