The formation of calluses is caused by an accumulation of dead skin cells that harden and thicken over an area of the foot. This callus formation is the body's defense mechanism to protect the foot against excessive pressure and friction. Calluses are normally found on the ball-of-the-foot, the heel, and/or the inside of the big toe.
Some calluses have a deep seated core known as a nucleation. This particular type of callus can be especially painful to pressure. This condition is often referred to as Intractable Plantar Keratosis.
Calluses develop because of excessive pressure at a specific area of the foot. Some common causes of callus formation are high-heeled dress shoes, shoes that are too small, obesity, abnormalities in the gait cycle (walking motion), flat feet, high arched feet, bony prominences, and the loss of the fat pad on the bottom of the foot.
Treatment and Prevention
Many people try to alleviate the pain caused by calluses by cutting or trimming them with a razor blade or knife. This is not the way to properly treat calluses. This is very dangerous and can worsen the condition resulting in unnecessary injuries. Diabetics especially should never try this type of treatment.
To relieve the excessive pressure that leads to callus formation, weight should be redistributed equally with the use of an orthotic. Effective orthotic transfers pressure away from the "hot spots" or high pressured areas to allow the callus to heal. The orthotic should be made with materials that absorb shock and shear (friction) forces. Women should also steer away from wearing high-heeled shoes.
As always, surgery should be the very last resort. If the problem persists, consult your foot doctor.