I just used hog panels all the way around on my pig pen they were not down in the ground....only had one pig in there the last two years we did a pig. Next year I think we will at least have 2 pigs in there. Right now it is opened up for the cows to be in a bigger area we did not raise a pig this year.
You maybe should put it down in the ground 6 inches they like to dig. You can put a hoop in their nose that hurts when they dig but I think it is mean and all they really have to do. They dig for many reasons. They need water of somekind when really really hot out cause they can't sweat to get cool so I had a little dirt hole pool in the middle of the pen and filled it up with water daily sometimes 2 times a day. I would spray the pig down too they like it just a mist. They like toys too old shoes, balls, old pieces of hose, old tires just the tire.
Good luck!