Glossary H

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

Hammer toes

Toes that are dislocated and look like the hammers in a piano. The problem is often seen in people with rheumatoid arthritis and results in ulcers on the tops of the toes and pain when walking.


Prominent tendons at the back of the knee that connect the hamstring muscles, which run along the back of the thigh, to the bones of the knee joint. The hamstrings allow the knee to bend and help the hip to extend.

Heberden’s nodes

Knobby growths of bone that commonly appear on the knuckle nearest the nail in people with osteoarthritis.

Hyaluronic acid

A substance in the synovial fluid of the joints that gives the fluid its viscosity and shock-absorbing properties. Agents to supplement hyaluronic acid, sometimes called viscosupplements, are used in injectable treatments for knee osteoarthritis

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