Arthritis Australia and run community seminars. Arthritis is an umbrella term for more than 100 medical conditions that affect the musculoskeletal system, specifically joints where two or more bones meet. The three most significant – osteoarthritis, rheumatoid arthritis and gout – account for more than 95 per cent of cases in Australia. The most common forms of arthritis are: Arthritis-related problems include pain, stiffness, inflammation and damage to joint cartilage (the tissue that covers the ends of bones, enabling them to move against each another) and surrounding structures. This can result in joint weakness, instability and deformities that can interfere with the
Reactive arthritis trachomatis" is the most common cause of reactive arthritis following urethritis. "Ureaplasma" and "mycoplasma" are rare causes. There is some circumstantial evidence for other organisms causing the disease, but the details are unclear. Reactive arthritis usually manifests about 1–3 weeks after a known infection. The mechanism of interaction between the infecting organism and the host is unknown. Synovial fluid cultures are negative, suggesting that reactive arthritis is caused either by an autoimmune response involving cross-reactivity of bacterial antigens with joint tissues or by bacterial antigens that have somehow become deposited in the joints. There are few clinical symptoms, but the