What Is Osteoarthritis?

What Is Osteoarthritis?

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What Is Osteoarthritis?

A normal kneeThere are about 100 different types of arthritis. In general, arthritis means problems with the joints. A joint is a point in the body where two or more bones come together. Arthritis may also cause problems in the tissue near the joints, including muscles, tendons, and ligaments. And, in some types of arthritis, the entire body can be affected.

Osteoarthritis (OA) is sometimes called degenerative joint disease, or wear-and-tear arthritis. It's the most common type of arthritis. In OA, the cartilage wears away. Cartilage is a slick tissue that covers the ends of the bones. It acts as a cushion and allows them to glide smoothly against each another. When the cartilage wears away, bone rubs against bone. This causes pain, swelling, stiffness, and difficulty moving.


A knee with osteoarthritisOA can affect any joint. Weight-bearing joints, such as the hips and knees, are often affected. Some common symptoms are:

  • Joint pain and stiffness.

    • Pain and stiffness may get worse with periods of inactivity or overuse. For example, people with OA have more stiffness first thing in the morning. And, many people have more pain in their hips or knees if they walk further than they usually do.

  • Weak muscles

  • Unstable or wobbly joints

  • Joints with swelling or bumps

  • Loss of range of motion, or the ability to bend and straighten them

If you have any of these joint changes, make an appointment to see your health care provider. The two of you can work together to create a treatment plan that can help lessen your pain and stiffness and prevent symptoms from getting worse.