Corns and calluses are the terms given to patches of hard, thickened skin. These can be located anywhere on your body, but they are typically found on your feet.
Corns are small, round circles of thick skin. They can develop on any area of your foot, but they are most commonly found on the tops and sides of your toes and on the sole of your foot. They occur more frequently on bony feet that lack cushioning.
Calluses are rough, very hard patches of skin. They are usually found on the heel or the ball of your foot, but they can also be found on your hands and knuckles. Calluses are usually bigger than corns and have a yellow color. They lack well-defined edges and may lack sensitivity compared to the rest of the foot.
What Causes Corns and Calluses?
Corns and calluses are both caused by friction and pressure. They are usually a protective reaction to prevent damage or blistering of the skin.
The most common cause of corns and calluses is ill-fitting shoes. Shoes that do not fit correctly or are too tight are likely to rub against your skin, causing friction. Excessive amounts of walking or running in well-fitting shoes can also cause corns and calluses, as can standing up for very long periods.
Women who wear high heels frequently are likely to suffer from calluses over the ball of the foot, because of the pressure put on this joint when walking.
Other possible causes of corns and calluses include manual labor, bunching of your socks or the lining of your shoes, not wearing shoes, or taking part in athletic events that put pressure on the feet.
Some people are more likely to get corns and calluses than others. People with bunions or hammertoes tend to be more prone than others. People who walk with overpronation (ankles roll inward too much) or oversupination (ankles roll outward too much) also tend to be more frequent sufferers. People who have damaged sweat glands, scars, or warts on their feet are also more likely to develop corns and calluses.