Callous

Feet

These are large, overgrowth and/or extensive rough patches of hard or tough skin (yellow or pale in colour) that can occur on any parts of the body that are constantly exposed to pressure or friction i.e. on a bone, shoes or against the ground.
It tends to be more of a burning sensation and uncomfortable, unlike a corn which is more painful.
If on the feet it tends to occur to those who stand, walk, jog a lot and those overweight, a common area on the feet are on the side of the heel and ball of foot.

Source: South West Podiatry

Source: Orangeville Foot Treatments | Orangeville Foot Clinic

Source: Best Callus Removers

Source: HealthLink BC

Source: You Ask the Question

Source: Softstar Shoes

Hands

If on hands or on knuckles it normally occurs to those who hold and work with tools or those who grip onto objects, i.e cross bar , dumbells in weightlifting and hand- held object sports i.e baseball, cricket , tennis, golf etc…

Source: Arthlete

Source: Golf Digest

Source: Medic Pole

Source: PrettySTRONG Powerlifting - WordPress.com

Knees

Source: Vintage Tradition

Source: Lipstick Alley

Symptoms

Does one have:

If on hands, is it on palms, an area constantly exposed to fiction and pressure or knuckles?

Is it on bony parts of body, constantly exposed to friction and/or pressure?

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