What is the difference between arthritis and osteoarthritis? Extremely similar pathologies, but with some critical differences. In both arthritis and osteoarthritis, the joints are affected. However, with arthritis, this lesion involves an inflammatory process that affects other parts of the body as well. Inflammation can be caused by infection, immune system abnormalities, or metabolic disorders. And osteoarthritis is a process that affects only the joints, but destroys them. That is why when arthritis is neglected, only a joint replacement can help a person🙌🏻