Callus

A callus (or callosity) is an especially toughened area of skin which has become relatively thick and hard in response to repeated friction, pressure, or other irritation. Rubbing that is too frequent or forceful will cause blisters rather than allow calluses to form. Since repeated contact is required, calluses are most often found on feet because of frequent walking. Calluses are generally not harmful, but may sometimes lead to other problems, such as skin ulceration or infection.

Common Calluses

Although usually found on the foot (where the most pressure and friction are applied), calluses can occur anywhere on the body as a reaction to moderate, constant “grinding” pressure. It is the natural reaction of the palmar or plantar skin. Too much friction occurring too fast for the skin to develop a protective callus will cause blisters instead.

People with bunions may find painful calluses behind the second or third toe. These are caused by unequal pressure and rubbing on the smaller toes. Such calluses can be very painful and often do not respond to trimming of the callus, soft materials, or orthotic devices. It is not the callus that causes pain, but rather the severe imbalance in the function of the foot that is taking its toll.

Shoes can produce corns by rubbing against the top of the toes or foot. Continued irritation may cause pain. Stretching out the shoe to reduce rubbing may reduce the contact and alleviate the pain, but the corn may remain. If a toenail rubs against the skin, pinching it between surfaces for a period of time, a corn can form at the edge of the nail. These corns are difficult to treat because the nail is frequently the primary cause.

Prevention

Corns and calluses are easier to prevent than to treat. When it is not desirable to form a callus, minimizing rubbing and pressure will prevent callus formation. Footwear should be properly fitted and broken in. People with poor circulation or sensation should check their skin often for signs of rubbing and irritation so they can minimize any damage.

Treatment

Calluses and corns may go away by themselves eventually, once the irritation is consistently avoided. They may also be dissolved with keratolytic agents containing salicylic acid, sanded down with a pumice stone, or pared down by a medical professional such as a podiatrist.

Wikipedia