What is a primary characteristic of osteoarthritis compared to rheumatoid arthritis?

Osteoarthritis is primarily characterized by localized wear and tear on the joints, which distinguishes it from rheumatoid arthritis. In osteoarthritis, the degeneration of cartilage and changes in the underlying bone occur primarily due to repetitive stress and age-related factors, leading to joint pain and stiffness. This form of arthritis often affects weight-bearing joints like the hips and knees as well as the hands, but it does so in a manner that is generally localized and not systemic.

This contrasts with rheumatoid arthritis, which is an autoimmune condition that typically results in symmetrical joint involvement and systemic symptoms, including fatigue and malaise. Morning stiffness in osteoarthritis usually lasts less than an hour, particularly improving with movement, while in rheumatoid arthritis, morning stiffness can persist for prolonged periods, often lasting more than an hour. Thus, the hallmark of osteoarthritis remains its localized nature and the wear-and-tear concept rather than systemic effects or symmetrical patterns of joint involvement seen in other types of arthritis.