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Types of Arthritis

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Browse the glossary by selecting a letter or by entering an arthritis-related term:


Chemicals in the body that aid immunity. When antibodies combine with invading agents, the complement system is activated to help . Complement levels are often low in people with lupus, for example.


A large protein that is the primary component of cartilage, tendons, skin and other connective tissues

Computed tomography (CT) scans

An imaging technique that provides the doctor with a three-dimensional picture of the bone. It also shows “slices” of the bone, making the picture much clearer than X-rays or bone scans.

Connective tissue disease

Any of a group of diseases characterized by degeneration of collagen – a key component of connective tissue, such as skin, muscles, tendons and ligaments. Connective tissue diseases include scleroderma, lupus, polymyositis and dermatomyositis.


A group of hormones, including cortisol, which are produced by the adrenal glands. Some regulate the body’s fluid balance; others influence the body use of fat and sugar (glucose). Corticosteroids can be synthetically produced and have powerful anti-inflammatory effects. They are not the same as the dangerous performance-enhancing drugs that athletes use to promote strength and endurance.

COX-2 inhibitor

A type of nonsteroidal anti-inflammatory drug (NSAID) designed to be safer for the stomach than other NSAIDs. COX-2 inhibitors work by inhibiting hormonelike substances in the body that cause pain and inflammation without interfering with similar substances that protect the stomach lining. Celecoxib (Celebrex) is the only COX-2 inhibitor currently available. Two others, rofecoxib (Vioxx) and valdecoxib (Bextra), were withdrawn from the market when it was discovered they increased risks from heart disease.

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