My GSD is 6 and rarely lays on tile or cement so I don't believe that it's that. It may just be from laying on anything. My elbows are rough toHans got this on both elbows when we were away for a week.
I used Penaten cream twice and now it is growing back in nicely.
Amazon.com: Penaten Baby Cream Crème Large, 5.1 Ounce: Beauty