The difference between osteoarthritis (OA) and rheumatoid arthritis (RA) Clinically, we often encounter patients with osteoarthritis and rheumatoid arthritis, in the early stages of the disease, there are some similarities, however, their pathology, symptoms, treatment, prognosis are significantly different, to summarize: 1, the pathogenesis of the two different: osteoarthritis is degenerative changes in cartilage (primary or secondary), rheumatoid arthritis is a systemic auto 2, the pathology is different: osteoarthritis is mainly in the cartilage, degenerative changes in cartilage, secondary synovitis, bone hyperplasia to form bone superfluous, in the heavier case caused by subchondral bone cystic degeneration, destruction; rheumatoid arthritis is mainly in the synovial membrane, synovial formation of vascular cataract gradually eroded to the cartilage and bone tissue caused by bone destruction. 3, the age of onset of different: osteoarthritis in the elderly onset of greater than 55 years of age group incidence of up to 80%, with age, gender, obesity and other closely related to the incidence of men before 50 years of age than women, after 50 years of age, women than men; rheumatoid arthritis onset of age 20 to 45 years old, to young adults, the ratio of men to women is 1:2 to 4; 4, the most commonly involved joints are different: osteoarthritis The most commonly involved joints in rheumatoid arthritis are the metacarpophalangeal joint, the wrist joint and the proximal interphalangeal joint, and rarely involve the distal interphalangeal joint; 5. The rheumatoid arthritis, in addition to the joints, can involve many organs of the body, such as the lungs, liver, heart, etc.; 6, different clinical manifestations: osteoarthritis starts slowly, gradually worsens, morning stiffness is short (less than 30 minutes), no subcutaneous nodules; RA in some patients with acute attacks, morning stiffness time is greater than 30 minutes, can appear subcutaneous nodules. 7, the two disease X-ray performance is different: osteoarthritis presents bone superfluous, visible joint space narrowing; RA is soft tissue swelling, bone erosion, joint deformation or subluxation. 8, laboratory tests are different: osteoarthritis generally no specific hematological changes, rheumatoid arthritis can appear, including rheumatoid factor, many autoantibodies; 9, synovial pathology is different: synovitis is characterized by synovial cell hypertrophy, hyperplasia, lymphocyte and monocyte infiltration; RA synovial formation of typical vascular opacities. 10, genetics are different: osteoarthritis and HLA in the various loci no significant correlation, while the development of rheumatoid arthritis and HLA-DR4 has a certain correlation; 11, medication and treatment response is different: rheumatoid arthritis treatment drugs are mainly slow-acting drugs, cytotoxic drugs, non-steroidal anti-inflammatory drugs are only applied when the pain. In contrast, osteoarthritis is dominated by non-steroidal anti-inflammatory drugs, slow-acting drugs and cytotoxic drugs applied to rheumatoid arthritis are ineffective or even harmful to osteoarthritis.