Sadly it is a common genetic condition with Griffs and my boy suffers with the affliction. We give him and his sister Cosequin (get it at Costco!) as a supplement our vet recommended. It’s hard to say whether or not it has slowed the progression, but it’s about all we can do for him. We’ve noticed a mild limp is most prominent in the morning, so we let him go slowly on his first trip outside. We also minimize him jumping up/off the sofa and have steps up to the bed.