dime size patch of black, hairless, leathery skin

Question
 I really appreciate you making yourself available to pet owners. Thank you.
 My dog has a small black hairless spot on his leg.The spot is About the size of a dime and has kind of a leathery feel. The dog licks the spot often, but the dog has always licked his legs/feet. If I had to guess I would say that it was a scar...
I was wondering about any skin conditions that may start this way or any thoughts you might have on this matter.
Thank you
John

Answer
What you are describing sounds like a callus. Without seeing it, of course it is hard to say. Callus' crop of from repeated trauma to an area. Over time, repeated friction or pressure anywhere on a dog's body will result in a protective formation of a tough, leathery area of skin. If what you are describing has cropped up seemingly overnight, you may be dealing with something other than a callus. A scar will have the same properties as a callous and it is an area that will most likely no longer grow hair and the skin can become tough.

You will want to check the area for bleeding, discharge, or swelling. Also check for tenderness in the area. If any of these are present, you may have something requiring a vet visit.

Callus are very common and normally something you wouldn't need to worry about. Preventing these (most notably on the elbows or rear haunches) is as easy as soft bedding! If the dry leathery area becomes cracked or bleeds, home treatment is as easy as cleaning with a 50/50 solution of hydrogen peroxide/water and a topical ointment such as bacitracin. Otherwise, you can work to soften the area with a bag balm or A&D ointment. Just keep in mind this will act as a dirt magnet when going outside and will have to be cleaned and reapplied after outdoor visits.

Since grooming is my main point of view, you may want to pose this question to one of the vet experts as well!