Thanks for the input! As I recall, the vet said that since Bella showed no signs of arthritis, her luxating patella is not painful or inflamed at this point in time. I did a quick internet search, and found the same information. Here is a quote from Kneecap Dislocation in Dogs | petMD :

"Typically, a dog with a dislocated kneecap will exhibit prolonged abnormal hindlimb movement, occasional skipping or hindlimb lameness, and sudden lameness.
The dog will rarely feel pain or discomfort once the kneecap is out of position, only feeling pain at the moment the kneecap slides out of the thigh bone's ridges."


I think that this standpoint is where my vet is coming from--she (the diagnosing vet) didn't want to overmedicate. But now that you have me thinking about it, I'll put in a call to the vet, just to be sure.

My pups and foster pups have always been given an anti inflammatory for patellar luxation flare ups. Every single case I have had has been given Metacam or Rimadyl and been put on cage rest. Most times they improve and the recommendation has been no surgery.....my vet and also the ortho vet I use tend to shy away from surgery on adult pups with patellar luxation.
As for pain meds, they were only given with a torn CCL but the surgery has happened within days so they were not on the meds for long.
Hope this helps.

Here are some more thoughts and opinion on the subject:

Human kneecap partial subluxations are almost always painful and almost immediately start an inflammatory process in the surrounding tissue of the joint once they progress past the earliest stage, which can turn to an enthesopathy, arthritic changes and more pain and dysfunction, which humans can usually successfully find a way to complain about unless they have a high tolerance to that type of pain and clearly, some do. Dogs can't tell us in words or necessarily use successful gestures so most vets observe how seriously injured or post-op or anesthetized dogs react as a leading indicator of how to evaluate pain in all lesser cases. I don't know how a veterinarian can determine a similar patellar subluxation in a canine is rarely painful using heart rate, respiration, lack of reaction to ROM or pressure or pupils or squinting or whatever other sign and symptoms he uses but even dogs with far more intensive injuries don't necessarily have any of those tell signs either according to vets I've asked.

Personally, I've been able to find little study of how canine pain is evaluated in veterinary circles and feel they under-study it in more routine orthopedic problems as they have stoic patients who rarely bug them for relief as humans do and funding is hard to find. I'm too fearful of leaving a dog in pain to accept the premise (or any veterinarian's opinion) that there is rarely pain and no inflammation when a dog is limping from a Stage IV subluxating patella that requires surgery to correct. And even accepting the premise, rarely doesn't mean all dogs don't hurt so I'd personally want to make sure my dog wasn't the exception as long as the dog was not bearing weight on the leg.

I'm not arguing with you or anyone and everyone must care for their own dog in the best way they feel comfortable - just giving more thoughts on the subject for readers to consider in how they plan to handle their dogs and question their vet about their dog's comfort when their dogs are not behaving normally and could very well be hurting from an orthopedic problem in an area which seems to be under-analyzed.