Editing Callus (section)

{{Short description|Thickened and hardened area of skin}}
{{About|calluses and corns of human skin}}
{{Missing information|evolution and biology|date=July 2019}}
{{Infobox medical condition (new)
| name            = Callus
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| image           = Evolucion de un callo.jpg
| caption         = Examples of callus found on the toe
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| field           = [[Dermatology]]
| symptoms        =
| complications   = Skin ulceration, infection
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| causes          =
| risks           =
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[[File:Calluses.jpg|thumb|Calluses (plantar in right foot and medial in left foot)]]

A '''callus''' ({{plural form}}: '''calluses''') is an area of thickened and sometimes hardened skin that forms as a response to repeated friction, pressure, or other irritation.  Since repeated contact is required, calluses are most often found on the feet and hands, but they may occur anywhere on the skin. Some degree of callus, such as on the bottom of the foot, is normal.<ref name=":0" />

Calluses are generally not harmful and help prevent [[blister]]s, as well as offering protection.<ref>[https://footwearnews.com/2019/focus/health/are-calluses-bad-for-feet-cracked-heels-1202801034/ Are Calluses Actually Bad for Your Feet? See What Podiatrists Have to Say], ''Footwear News''</ref> However, excessive formation may sometimes lead to other problems, such as a [[Ulcer (dermatology)|skin ulceration]] or infection, or cause the affected person to try to offload the affected painful area, which can place excessive stress on the asymptomatic side.

Rubbing that is too frequent or forceful will cause [[blister]]s, as opposed to calluses, to form.