Corn and callus

Author: Dr Amanda Oakley, Dermatologist, Dept of Dermatology Waikato Hospital, Hamilton, New Zealand, 2005.

What is a corn? What is a callus?

Corns and calluses are common skin lesions in which there is a localised area of hard, thickened skin.

What causes corns and calluses?

Corns and calluses are caused by response to friction and pressure. Repetitive injury results in the skin trying to protect itself from blistering. The basal epidermal cells (keratinocytes) increase in number resulting in thicker prickle cell layer and thicker stratum corneum.

The most common site for a corn or a callus is on the hand or foot, but any area of skin may be affected. Examples include:

Thick skin on the entire palm or sole is known as palmar or plantar keratoderma. This term is also used for genetic disorders in which there are multiple areas of callus (punctate keratoderma).

See more images of corns ...

What is the treatment for a corn or callus?

The important thing is to relieve the pressure on the affected area of skin.

Reduce skin thickness.

Ease the discomfort of painful cracks (fissures)

It may be helpful to visit a podiatrist for treatment of a callus or corn on the foot.

Sometimes protruding bone has to be surgically removed by an orthopaedic surgeon, for example bunion repair.

Related information

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