The Different Types of Arthritis
As you now know, arthritis is an inflammatory condition of the joints of the body. However, arthritis is not a disease. It is a combination of symptoms that, when there is objective evidence (x-ray or blood test) to demonstrate its presence, allows a conclusion to be drawn as to the exact nature of the condition. And because there are many symptoms associated with arthritis, there are many different presentations and, therefore, many different classifications (or diagnoses) of arthritis. In fact, there are over 100 different types of arthritis. The most common are listed below.
Osteoarthritis occurs when there is a thinning, breakdown or loss of the cartilage covering one or more of the joints within the body. Cartilage is a flexible connective tissue composed of specialised cells that, when acting as a surface for joints, offers a frictionless surface for joint movement. Because cartilage repairs slowly (due to the absence of blood supply), with age, trauma or injury the cartilage may wear away. When this happens, inflammation is produced, tendons and ligaments may stretch and bone erosions may result, producing the pain associated with arthritis. Osteoarthritis most commonly affects the hands, feet, spine, hips and knees.
Rheumatoid arthritis predominantly involves flexible, synovial joints (joints that have fluid within them, such as knees, hips, shoulders, feet and hands). There is destruction of joint cartilage as a result of aggressive inflammation, which may be initiated by the body itself, resulting in rheumatoid arthritis being classified as an auto-immune disease.
While rheumatoid arthritis most commonly affects the joints mentioned above, any joint can be affected. It also affects the organs, including the lungs, kidneys, heart and blood vessels.
Juvenile Rheumatoid Arthritis
Juvenile rheumatoid arthritis (JRA) is similar to rheumatoid arthritis, except that it affects children 16 years of age or under. There are three principal types of JRA:
Gout is usually characterised by acute, recurrent painful attacks to a single joint, most commonly the big toe or other joints of the feet. The joint is usually red, swollen and painful to touch. This results from uric acid depositing in the joint and crystalising, creating inflammation and damaging the tissue.
Ankylosing spondylitis is a chronic inflammatory condition primarily affecting the spine and is associated with ligaments becoming increasingly rigid and eventually fusing, resulting in complete rigidity of the spine. The cause is unknown, though it is suspected there is an auto-immune element involved.