I would start with PROMAXOL. It helps to decrease pain, inflammation, and stiffness and stimulate healing. Initially I would give a half dose with breakfast and supper. After improvement is seen you can decrease to a whole dose once daily. For longer term management you can switch to ARTHRO-IONX. In addition I find it helpful to follow a holistic approach by giving some nutritional supplements to accompany the homeopathic. I would use MSM, vitamin C, probiotics and Omega 3,6,9, I also use a glucosamine product that contains Perna mussel if the joint needs rebuilding. What do you feed and give as treats? Diet can make a difference.
I would also suggest an evaluation by a veterinary chiropractor. If a correction is needed, that can help with better movement. Acupuncture can be beneficial as well.