I used herbs and supplements as an alternative treatment for the treatment of canine arthritis in the country. Stem cells will be the next treatment for osteoarthritis if your herbal treatment stops working.
Beware of veterinarians who only give painkillers like COX2 inhibitors! There are supplements and herbs that can rebuild cartilage or stop it from decomposing, while also downregulating COX2. You owe your dog a vet up to speed on his reading.
The next main thing as a home arthritis treatment for your dog is the high repetition movement of low load. That may be swimming or manipulation of the passive joint. I forgot to emphasize in the video, but I must recondition the arthritic joints with supplements for a few months before building muscle with exercise. Until that happens, use passive joint manipulation only.
Do not use corticosteroid injections. Help a little, break the joint tissue later.
Video credits to SashaAndCo YouTube channel