Hyperkeratosis of the heel. Hyperkeratosis describes a thickening of the outer layer of the skin caused by abnormally increased amounts of the protein keratin which normally functions to protect the skin.

Licence: Attribution 4.0 International (CC BY 4.0)

Credit: Hyperkeratosis of the heel. Hyperkeratosis describes a thickening of the outer layer of the skin caused by abnormally increased amounts of the protein keratin which normally functions to protect the skin. Geraldine Thompson. Source: Wellcome Collection.