I have a female GWP that's almost 11 years old and she's been taking Proin since developing urinary incontinence after being spayed at approximately 6 months. Her health problems include dysplastic hips, and torn cruciate ligaments in both knees at around 3 and 4 years of age, but I've never heard of Proin being associated with joint problems in canines, so she seems to have handled her daily Proin dose OK.
Good luck!
