I was thinking possible luxating patella also. A vet can diagnose this very easily and quickly. Some dogs live with it just fine. You just have to be careful. My 4 yr old yorkie has grade 3 luxating patella in both back legs. She has very little problems with it though. It might be worth having it checked at least.
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Maggie (RIP), Ginger (RIP), Lilly (RIP), Bella (RIP), Saleen, Bailey, Bridget, Lucy |