【Rheumatoid arthritis (RA) is an autoimmune disease in which the body’s immune system – which normally protects its health by attacking foreign substances like bacteria and viruses – mistakenly attacks the joints.】 This creates inflammation that causes the tissue that lines the inside of joints (the synovium) to thicken, resulting in swelling and pain in and around the joints. The synovium makes a fluid that lubricates joints and helps them move smoothly.

【风湿性关节炎是一种自免疫系统的疾病——它本来会正常保护身体免受细菌和病毒的干扰——错误攻击了关节】。
【Osteoarthritis is a joint inflammation that results from cartilage degeneration.】
【Osteoarthritis can be caused by aging, heredity, and injury from trauma or disease.】

【骨关节炎是由于软骨结构退化造成的关节部分炎症。】
【骨关节炎可能因为年老、遗传、或者由于疾病或外伤造成的损伤而导致。】
【Osteoarthritis is abbreviated as OA or referred to as degenerative arthritis or degenerative joint disease (DJD).】

【骨关节炎简称OA,或者也经常叫做退行性关节炎/关节病(DJD)】

所以你还要说风湿性就是指部位是关节、而不是指病因么?

自己看看风湿性关节炎和骨关节炎/退行性关节炎的病因相同不相同。。