Corns and / or callus are one of the more common problems seen by podiatrists. They can occur on any part of the foot that touches a hard surface such as the ground or a shoe. They can vary in severity from a mild callus under the foot to an infected ulcer that has developed under a corn. The Latin names for corns and callus are hyperkeratosis, clavus, heloma and tyloma.
Pathologically, all of the above are all the same – the skin has thickened in response to excessive pressure. A callus generally refers to a more diffuse thickening of the skin (like standing on a thin coin) whereas a corn is a thicker more focal area area (like stepping on a pebble).
A corn or callus is an area of thickened skin that occurs in areas of excessive pressure. It is a normal and natural way for the body to protect itself from all of the skin being flayed away and exposing the bone below. Only one hundred years ago, exposing the bone in the foot may well have lead to death. Problems only occur when too much pressure continues and eventually becomes painful.
The excessive pressure can be from causes such as:
• wearing footwear that is too tight
• toe deformities, such as clawed toes -which lead to increased pressure on the top of the toe
• bony prominences touching the ground or the shoe
• abnormalities with the biomechanical or gait that cause more pressure at some areas of the foot.
Corns and calluses that are not properly treated will become increasingly painful. They will not resolve on there own. If the pressure becomes too much, the skin below the corn may die and start to weep, causing an ulcer. This can be a significant complication for those with poor circulation, peripheral neuropathy or diabetes foot.
As corns & calluses are symptoms of underlying mechanical problems, self treatment will often ignore a proper diagnosis of the underlying cause.
Home treatments such as corn paint or plasters contain acid that are supposed to ‘eat away at’ the corn. The corn is much tougher than normal skin and so is more likely to sear away the good skin and leave the corn in place. This can be risky in healthy people but it is very dangerous in those with poor circulation and healing as can occur with diabetes. The use of corn pads in those who are have frail skin are very likely to cause an ulceration which could become infected and it lead to amputation.
Our treatment of corns and callus includes assessment to determine the cause of the lesion formation of a management plan including
• regular removal of the corny tissue
• use of padding to deflect away pressure
• advice about proper fitting of footwear
addressing bony prominence that may be causing the high pressure area
It is essential that those with diabetes and/or poor circulation see a podiatrist for the management of their corns and callus.