Our Buffy has luxating patellas in both back legs. She was in quite a bad way - although it didn't seem to bother her, just us - as her legs used to go "out" all the time. She never went far from us as a baby and would scream if any other dogs came close. Then we discovered hydrotherapy!
She is like a completely different dog. She is confident, runs around, chases anything that moves and her legs seem so much stronger than ever before. She is always going to have the weakness I am sure, and the vet says if he operates, she will have to be crated 24/7 until the first leg heals (just out for wees on a lead) then the same with the other leg. Then she would probably get arthritis when she is about 7 or 8 years old.
If he doesn't operate, she will probably get arthritis when she is 7 or 8 years old!!!!
Therefore, so long as nothing else happens, she is not having the op - just the hydrotherapy. At the moment she goes once or twice a week, but we hope that will get less as she gets older.
There is no way I would ever dream of breeding from her - she is incredibly lucky as she is really small and light (measuring just over 10" at the shoulder!) and as she is now 15 months old, I don't think she will get much bigger than this.
Her parents were both tested once this problem was discovered and both were clear, but her breeders are still not going to put that pair together again (as far as I know anyway) just in case.
It has been incredibly worrying, and expensive (hydro sessions are not cheap and we are still waiting to hear about the insurance company covering it and if so how many sessions) and I would not swap Buffy for the whole world - but to put any extra strain on her legs? No way.
Sorry, just my opinion, but you did ask.