The most typical site of involvement in rheumatoid arthritis is the wrist, which is the most commonly involved site, especially in Asians. Small joints such as the wrist, metacarpophalangeal joints, and proximal interphalangeal joints are the typical sites of involvement and are often symmetrical. The distal interphalangeal joints of the small joints are rarely involved as a feature of the disease. In addition to the small joints such as the wrist, metacarpophalangeal and proximal interphalangeal joints, the cervical spine and temporomandibular joints can be involved, causing difficulty in opening the mouth. It is also very likely to occur in the toe joints, and in the large joints, such as the knee, even the knee in the first instance, which accounts for more than half of the synovial membrane in the body, and the knee, hip and ankle joints may be involved. So when it comes to swollen wrist joints, the most first thing that comes to mind is rheumatoid arthritis.