Bumps on Cat's back - Please help!

Hi, over a year ago my cat got into a fight and small bumps developed along her back/side where she was attacked. I took her to the vet and she was given antibiotic treatment, although the wounds healed up the bumps remained after the treatment was finished. The vet did not know what it was, so they did a Biopsy. The results didn't come back with anything conclusive; they said it looked like the cells weren't cancerous although that couldn't be ruled out. Since then we have tried long term antibiotic treatment which had minimal results, and now are trying steroid treatment which seems to be helping a bit, but not fully fixing the problem. The small bumps are still there, there is no drainage or scarring at the night, and other then the bumps the cat is healthy as could be (She is a 6 year old fixed domestic female). When you touch the bumps excessively the cat seems irritated, and sometimes you can see that area twitching. This is a huge mystery to me and my vet so if anyone has experience something similar or has any advice PLEASE share because we are running out of options.

Could you upload photos of these bumps?
Sounds weird to me, like they're scars but then why would the vet biopsy them?