I have a 11 year old Dalmatian. Purdy is her name, she had knee surgery in 2005 and was starting to have problems walking on her right back leg (the bad knee). She fell down 4 steps becasue her knee gave out. We took her to the Vet becasue she could not walk. He has given her joint meds and pain meds for about 2 weeks we took her back and he said she need surgery again on that knee, but not sure what is wrong with it for sure until he gets inside (They took x-rays) She also has arthritis in her hips. What do you think we should do, have another costly surgery?

Thanks in advance