6mth out-of-date feminine cat have "popping" nouns surrounded by front leg? Anyone enjoy concept? Experience?

We're going to the vet again today for the 2nd time since this started about 3 weeks ago. I'd like to hold an idea going in there what we might be dealing next to. The sound is like a pop, just similar to in people when your knee or knuckles crack and pop. At first it be just the sound, but we took her to the vet immediately. He found nil, advised us to watch it. Now it appears that she's favoring that leg with a bit of a flaccid. She's only 6mths old, very dainty, slightly active. This sound developed right after she was spayed. It doesn't "pop" when she runs or jump, only when she walks slowly. I've had cats my entire life span and never experienced this. Has anyone ever heard of such a thing?

Mice problem- would a cat back?
Answers:    I have never have a cat w/ this, but heard my vet discuss it... luxating patella. This can be inherited.

LUXATING PATELLA: The patella (kneecap) is displaced from its normal position any by force
or spontaneously. This may recur if the trochlear groove is shallow or malformed. It may correct
itself and cause lone temporary discomfort or it may require surgery if the condition recurs or
cause lameness. Cats with luxating patella have a greater tendency to hip dysplasia than those
minus.
My cat keep meowing at me, what...
Is very possible that your kitty was pinched by something or by another animal and it hurts like Hell! can be splinter, pin, sewing pin, tiny stone, its own nails etc. with extreme care examine its leg and try to find the wound. However you own to take the kitty back to the vet and show the problem. I hope this advice will give support to you.
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