I have the same patch on one Shin that my former GP said was Psoriasis. When this appeared, I was at my worst Crohn's wise. It was deep in the flesh and black with the red surface and scaly. I have never had anything like it before. The really odd part is my brother has exactly the same thing, in the same place. He does not have Crohn's.
Now is it just red near the surface and scaly and it does also itch on occasion. It is improved over what it was, but it never goes away altogether.
I still am not convinced it is psoriasis, as I have never seen a case of psoriasis that has gone deep into the tissue.
I have never treated it to any degree, as I figure it is a Crohn's early warning system. If I am flared, I assume it will get wore also. I have put various lotions on it, but that makes it worse, and it itches more.
I think I will start treating it myself, but as I do not know the direct cause, it makes it a hit and miss approach. Not the way I like to go about it.
Now I wonder, is is Psoriasis or PG?
Dan