Clive Anderson - AT THE DERMATOLOGISTCORNS AND calluses are the most common foot problems. A corn is a thickening of the surface layer of the skin in response to pressure. Corns commonly form where bones are prominent and the skin is pressed against the shoes, ground or another bone. As a result of this pressure the body forms a cushion of thickened skin between the two hard surfaces.
A callus is a similar but more diffuse structure. Corns and calluses then are the body's natural means of protecting itself from trauma. Calluses will develop on the hands of persons who do manual labour. On the foot the corns and calluses develop in areas of pressure. As the skin gets thicker it presses on the underlying tissues and may cause pain.
Hard corns are located on the outer surfaces of the toes usually and appear as a horny thickening of the skin. Often the corn is darker coloured than the surrounding skin. Corns may also occur between the toes, these are called soft corns. Soft corns often are mistaken for fungal infections between the toes. This lesion, however, does not respond to
antifungal treatment.
The pressure on the skin that causes a corn or a callus may result from:
Too tight shoes.
Toe deformities such as hammer toes that result in a portion
of the toe being pushed against
the shoe.
A bony prominence.
Gait abnormalities that cause pressure to be distributed unevenly on some areas of the bottom
of the foot.
Seams or stitches in the shoe which rub against the toe.
Prolonged walking on a downward slope.
Corns may develop an ulcer that extends as far as the bone. They may also become infected. Serious infection may ensue, especially in persons with diabetes or diminished circulation in the foot. It is much easier to prevent corns than it is to treat them once they have formed.
Wear shoes made of soft
material.
Choose shoes with extra cushioning in the heel and ball of the foot. This keeps the foot in a natural position.
Pick shoes with wide rounded toes. This reduces the pressure between the toes.
Avoid shoe heels higher than 21/4 inches.
Ensure that the lining of the shoe is smooth.
Avoid narrow toed shoes, they are likely to cause corns, bunions, foot pain and arch problems.
Dry thoroughly between the toes and wear absorbent cotton socks.
Go barefoot when possible. This allows the toes to splay out and remove the pressure between the toes.
Correct any underlying foot deformity.
Corns are treated by reducing the bulk of the horny tissue. This may be done by using physical methods of paring down the tissue or chemicals that gradually breakdown the thick mass. Often both methods are used. The patient is prescribed a solution containing salicylic acid to paint on to the corn. Covering the area with a bandage may allow for better penetration. After a period the foot is soaked in water for a few minutes. The dried corn is then rubbed with an emory board or nail file thus removing all the now crumbly tissue.
Repeated treatments like this will gradually remove the corn. Care must be taken not to be too aggressive with the treatments as an infection may occur. This is especially true in diabetics or persons with reduced circulation in the feet. These persons are best treated by a Podiatrist. If the source of the pressure on the foot is not removed the corn will recur.
Dr. Clive Anderson is a Dermatologist and Venereologist.
