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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:

T cells

A type of white blood cell involved in immunity. T cells mature in the thymus and have the ability to recognize specific antigens through receptors on their surfaces. Also called T lymphocytes.

Tai chi

An ancient Chinese practice that involves gentle, fluid movements and meditation to help strengthen muscles, improve balance and relieve stress.

Tender points

Specific areas of the body that are particularly painful upon the application of slight pressure. The finding of tender points is useful in the diagnosis of fibromyalgia.


The inflammation of tendons – strong bands of connective tissue that attach muscles to bones or muscles to muscles


Thick connective tissue that attaches muscles to bones


The shin bone or larger bone of the lower leg. The tibia is one of three bones (the other two are the femur and the patella) that join to form the knee joint.

Transcutaneous Electrical Nerve Stimulation (TENS)

A treatment for pain that uses a small battery-operated device to direct mild electric pulses to nerves in the painful area. The theory is that the mild electric pulses will block the transport of pain signals from nerves to the brain.

Tumor necrosis factor (TNF)

A cytokine (chemical messenger) in the body that plays a role in inflammation and tissue destruction in diseases such as rheumatoid arthritis, but also is important for normal function of the immune system. Blocking TNF with biologically derived drugs, called TNF inhibitors, has proven to ease symptoms, inhibit joint destruction in RA and halt the progression of disease.

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Juvenile Arthritis information & resources

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Just For Kids

A website for kids, tweens, and teens with arthritis

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