Also known as degenerative joint disease mostly affects older dogs. In a healthy dog, a coating of cartilage protects the connecting surfaces of a joint. This allows the bones to move smoothly over one another reducing friction. When osteoarthritis is present the cartilage around the joint is often damaged. This creates friction as bones make contact with each other, leading to inflammation and further soft tissue damage.
The constant rubbing of the bones can cause bony spurs to develop around the affected bone surfaces causing further pain, inflammation and reduced mobility. Reduced mobility can lead to loss of strength in supporting muscles and ligaments becoming slack. Reduced mobility can also cause dogs to put weight on increasing the stress placed on the joints, including elbows, hips, Stifle (knee joint), shoulders, Carpus (wrist), Hock (ankle) and intervertebral joints (backbone).