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I rescued my jack russell/min pin/chiuaua/basenji mix last year. The vet said that his knees were, "a little loose" but he is in good health. He also has food sensitivity issues (which we have corrected) and he is 2 years old. I Googled "loose knees in Jack Russels" and found out that it is common in dogs who like to jump a lot...when they do, the hind joints frequently rotate causing looseness in the joint OR displacement of the patella. My dog LOVES to jump around and I am wondering what I can do to help prevent the onset of arthritis for as long as I can? He is a jumper...it is in his innate makeup...so what can I do?