Calluses and Corns
The skin protects the body from many threats and stresses. In places where the outer layer of skin is exposed to stress (especially the effects of pressure and shear force or friction), the body adapts by forming a callus (tyloma)--a thickened area of skin that protects the exposed location. On the feet, calluses commonly occur on the toes, the ball of the foot and the heel.
“Soft" corns often occur on the sides of toes that adjoin other toes, where friction or pressure is present. Although callus formation is a natural reaction of the body to pressure and friction stresses, it is important not to allow them to become too large or painful.
People with diabetes should be aware that corns and calluses can set the stage for foot ulcers.