Arthritis is a joint disorder featuring inflammation. A joint is an area of the body where two different bones meet. A joint functions to move the body parts connected by its bones. Arthritis literally means inflammation of one or more joints.

What Cause Arthritis?

Arthritis is not one disease with one cause. There are several  different types of arthritis, each with its own cause. Bacteria can sometimes cause a severe acute infection called infectious arthritis. Men with hemophilia can have bleeding inside their joints, which over the years can cause a severe arthritis. One particularly severe and sudden type of arthritis, gout, is caused by crystals of a chemical called uric acid being deposited inside a joint.

Rheumatoid arthritis is a specific form of inflammatory arthritis, it is caused by your own immune system, which starts (for no known reason) to attack the delicate membrane lining the inside of your joints. Because rheumatoid arthritis is caused by your body attacking itself, it is referred to as an autoimmune disease.

Symptoms

Arthritis-related joint problems include pain, stiffness, inflammation and damage to joint cartilage (the tough, smooth tissue that covers the ends of the bones, enabling them to glide against one another) and surrounding structures. Such damage can lead to joint weakness, instability and visible deformities that, depending on the location of joint involvement, can interfere with the most basic daily tasks.

For many people with arthritis, however, joint involvement is not the extent of the problem. Many forms of arthritis are classified as systemic, meaning they can affect the whole body. In these diseases, arthritis can cause damage to virtually any bodily organ or system.