is an abnormal thickening of skin. They say it is because of the excessive pressure applied on a particular area; however it may not be the reason in all the cases.
Excision or surgical removal is one of the methods to eliminate the callus. However, in some cases they may reoccur.
You may also try using corn
caps and application of salicylic acid
on the affected area.
Another method is to dip your leg in warm water for 15-20 minutes and peel off the callus using a pumice stone.
In Ayurveda, there is a procedure called "Agni-Karma" where the corn/callus is removed. You may have to consult a specialist for it.
Please start wearing MCR footwear.