Jazz needs knee surgery

Jazz was abandoned as a puppy. She came to live with us when she was 12 weeks old. Because she is a mutt, her legs have given her many problems. She has gone through four surguries on one knee. She ruptured her ACL when she was only 4 years old. The first surgery should have fixed it, but there were complications. We finally have that leg healthy and now she has ruptured the ACL in the other knee. The vet had said there was a very good chance that would happen. She is in perfect health otherwise. She is now almost 9 years old and needs surgery again. I can't bring myself to put down a sweet lovable dog just because she has bad knees. It will take around $3000-$3200 to fix her knee. If anyone would like to pitch in and help us fix this poor dogs leg, it would be greatly appreciated.