Here is a photo of my knee bent in what I think is a very similar position.  There are some smallish bumps there that you probably can't see from my pant leg I was sitting on - but the overall flesh squishing there is just not nearly as extreme.

Also DP I took your render and circled problem areas.  If you don't mind I will repost that here but I don't like drawing all over other peoples work without permission.

I am:  aka Velocity3d