Calluses are formed from the build up of dead skin cells that harden and thicken on the surface of the foot. Calluses are the body's defense mechanism for protecting the skin agains excessive friction and/or pressure. These formations are commonly found on the ball of the foot, the outside of the big toe, and/or the heel. Sometimes there can be a deep seated reason for calluses known as nucleation, also called Intractable Plantar Keratosis. These types of calluses can be extremely painful to pressure.
Excessive pressure at any specific area of the foot can cause calluses to develop. A few common causes of callus formation are high-helled dress shoes, shoes that are too small, obesity, abnormalities in the gait cycle (walking motion), flat feet, high arched feed, bony prominences, and the loss of the fat pad on the bottom of the foot.
Treatment and Prevention
Some people try to reduce the pain caused by calluses by cutting or trimming them off. This is absolutely not recommended nor is it the proper way to treat them. Cutting or trimming calluses are very dangerous and can even worsen the condition, even result in unnecessary injuries. Diabetics especially should never try doing this themselves. The safest method to reduce excessive pressure that leads to callus formation, is to equally redistribute your body weight through the use of orthotics. Effective orthotics will transfer pressure away from any "high pressure points" to allow any calluses to heal. Orthotics should be made of materials that are capable of obsorbing shock and friction.
If the problem persists, consult your foot doctor.