Any BB Vets about? Luxating patella question, worried.....

Holly my maltese cross is 4 in December of this year. About 6 weeks ago I came home to notice her favouring her left back leg - I was only out for 20 minutes, so thought she must have jumped akwardly or something. She walked on it normally mostly and by the end of the week, I hadn't noticed any favouring at all. Over the past 6 weeks, I've noted a little bit of occasional limping - maybe once a week, twice at the most, still wanting to chase her ball and play and go walking.
She's always had clicky joints and lies like all Malteses that I know with her legs straight out at the back. Today however, she seems to be favouring the leg alot - not putting weight on it while eating her dinner (no appetite loss at all) , when I picked her up, and felt the knee, I felt a kind of pop.

She will be going to the vet next week for vaccinations, and I will get it checked, but a google search has me a bit scared - could it be luxating patella or are there other things that cause this?

Is glucosomene worth using?

If we had to go the surgery path, worse case, how expensive is this going to be?

Thankyou!!

Hi Ausgirl - I am not a vet but did vet nurse for a number of years. It could be something like a patella ligament but it could be really anything. Only an examination would be able to tell. I would take your dog in earlier to the vet (it doesn't matter if vaccinations are a bit early) because if she is holding it up then it must be quite painful. I wouldn't worry about using glucosamine as it would take a couple of months for her to get any benefit and it wouldn't provide any pain relief or help if her patella/cruciate etc has gone. It is a reasonably common procedure but can be pricy depending on the vet. I think from memory they were around a thousand when I used to nurse but it would be so dependent on the vet, the procedure, and the needs of the animal.
Sorry I couldn't help more!

luxatting patellas can be very costly $$$$$$$
small breed dogs (maltese expecially!!!!!) are prone to luxatting patellas
been through it many years ago when we used to breedminiature pinschers, i have since moved onto breeding/showing boxers