Nikki,
I am so sorry to hear about your little girl yorkie...I don't have any answers for you, but I am praying that you will get the advice that you need. The only thing I know about prednisone is that it's pretty effective, but the downside is that their immune system goes down big time...I'm not sure about long-term use of Metacam...I will be saying a prayer for your little mush mouse