The term "arthritis" refers to over 100 different conditions that affect the joints (the places where 2 bones meet). Some forms of arthritis may also affect other areas of the body, such as the skin, heart, or kidneys. Often, arthritis is a long-lasting disease, affecting people over many years. Symptoms often include pain, stiffness, swelling, redness, and heat in the joints.

Although the disease process for all forms of arthritis differs from person to person and from disease to disease, all types of arthritis have certain features in common, which sometimes makes them difficult to accurately diagnose. Regardless of the type of arthritis, it is important to diagnose early so that treatment can be started.

The 2 most common forms of arthritis are osteoarthritis and rheumatoid arthritis

Osteoarthritis (OA), also known as degenerative arthritis or degenerative joint disease, is the most common type of arthritis, affecting 1 in 10 Canadians. Although OA can develop at any age, it usually develops after the age of 45, affecting both men and women equally. Cartilage deterioration in one or more joint is responsible for OA, leading to joint damage, pain, and stiffness. OA usually affects the knees, hands, feet, spine, and hips.

Rheumatoid arthritis (RA) affects approximately 1% of Canadians. It usually strikes between the ages of 25 and 50. Women are at least twice as likely as men to get RA. RA is progressive, which means that it gets worse over time. Symptoms, which include stiffness, swelling, pain and joint damage, are a result of the inflammation of the joints in the body. It may also affect other areas of the body, including the heart, eyes, and lungs. RA is called an autoimmune disease because it is your body's own immune system that is fighting itself. RA can cause severe disability in some people, but it can be managed through medications and other treatments.

Some other types of arthritis

Psoriatic arthritis usually occurs between the ages of 20 and 50. Men and women are equally likely to get psoriatic arthritis. Psoriatic arthritis usually starts out as psoriasis, a condition where areas of the skin become inflamed and covered with silvery grey scales. The fingernails may also be damaged. In some people, arthritis may show up first. The joints most often affected include the knees, ankles, wrists, fingers, and toes. The spine and sacroiliac joints (the joints between the spine and hips) may also be affected.

Infectious arthritis affects both men and women, and can occur at any age, causing joint inflammation (swelling and pain). A germ such as a bacterium, a virus, or a fungus causes infectious arthritis by travelling into a joint, usually large joints such as shoulders, hips, and knees, where it causes inflammation. Infectious arthritis may also affect smaller joints of the fingers and ankles. Usually, if treated early, the symptoms are not long-lasting.

Children can get arthritis

Arthritis is not just a "senior's disease." Juvenile arthritis is a general term for all types of arthritis that affect children. This includes many types of arthritis, such as juvenile rheumatoid arthritis (JRA), childhood forms of lupus, ankylosing spondylitis, and others.

JRA affects children 16 years of age or younger, and is the most common form of arthritis in children. Symptoms usually do not last a lifetime and tend to disappear after several months or years.

Written and reviewed by the MediResource Clinical Team