I'm not sure what it is exactly but I did a little image search and I found the closest thing to this is something called Psoriatic Arthritis.
I personally get something like this (similar) sometimes it's like a scab and it itches but I do have keratosis pilaris (I notice it happens when weather changes and when my arms are exposed to moisture and I do not dry them)
I think you should check up with your family doctor or a dermatologist to check it out for you!
