now had a chance to look at the article.
If tame, very lame and old, I'd suggest that your chances of fixing this are very slim. Old pigs are not good on their legs, and it may (or may not!) be the reason why she was kicked out in the first place.
Given that you are a sanctuary, suggest you try for a week, and make sure that you get some metacam to both relieve pain and as anti-inflammatory (version for pigs the formulations are different between animals- your vet will supply), it comes in two versions as an injectable or as oral. The injection is better if you can administer jabs, but otherwise go for it as a liquid that you can put into feed/onto food.
After that I'd very seriously consider having her put down, and if it doesn't improve in a week, it's highly unlikely to, and an animal that lame will be in constant pain. Pigs don't walk at all well on 3 legs, the weight is at each corner and the anatomy prevents them repositioning to compensate (as say a dog would), and if she's overweight as well that will just make everything worse..