Arthritis refers to the inflammation of one or more joints. The most common type of arthritis in dogs and cats is osteoarthritis, also known as degenerative joint disease (DJD). In pets with osteoarthritis, the cartilage lining at the end of the bone deteriorates and the surrounding fluid thins, causing inflammation, pain, and stiffness where the bones rub together. The bone can wear down, develop bone spurs or even chip as osteoarthritis progresses.
Hip dysplasia is a skeletal disorder that results in instability or looseness of a dog’s hip joint. The hip joint normally functions as a ball and socket but, in dogs with hip dysplasia, the ball and socket do not fit properly — instead of rolling and sliding, they rub and grind.
Since the bones of the joint don’t line up correctly, the joint cartilage is subjected to abnormal wear and tear. Over time, cartilage damage occurs, resulting in pain and arthritis.