Osteoarthritis, sometimes called OA, is a type of arthritis that only affects the joints, usually in the hands, knees, hips, neck, and lower back. It's the most common type of arthritis.

In a healthy joint, the ends of the bones are covered with a smooth, slippery tissue called cartilage. The cartilage pads the bones and helps them glide easily when you move the joint. With osteoarthritis, the cartilage breaks down and becomes rough. Sometimes, all the cartilage wears away and the bones rub together. Bumps of extra bone called bone spurs may grow in the joint area.

There is no cure for osteoarthritis. It usually gets worse slowly. But there's a lot you can do to manage the symptoms.

Osteoarthritis affects people in different ways, and not everyone has pain. The most common symptoms are:

• Pain when you move, which often gets better with rest
• Stiffness, especially for the first 30 minutes after you get up from resting
• Swollen joints, especially after using the joint a lot
• Less movement in the joint than normal
• A joint that feels loose or unstable

Researchers aren't sure what causes osteoarthritis. They think that it could be caused by a combination of factors in the body and the environment. Your chance of developing osteoarthritis increases with age. They also know that some people are more likely to develop it than others.

Things that make you more likely to develop osteoarthritis include:

• Aging. Osteoarthritis can happen at any age, but the chance of getting it increases in middle-aged adults and older. After age 50, it is more common in women than in men.
• Being overweight. Extra weight puts more stress on your joints.
• Having a past injury or surgery on a joint. This is often the cause of osteoarthritis in younger adults.
• Doing a lot of activities that overuse the joint. This includes sports with a lot of jumping, twisting, running, or throwing.
• Having a joint that doesn't line up correctly.
• A family history of osteoarthritis. Some people inherit genetic changes that increase their chance of developing osteoarthritis.

There is no specific test for osteoarthritis. To find out if you have osteoarthritis, your provider:

• Will ask about your symptoms and medical history
• Will do a physical exam
• May use x-rays or other imaging tests to look at your joints
• May order lab tests to make sure that a different problem isn't causing your symptoms

The goal of treating osteoarthritis is to ease your pain, help you move better, and stop it from getting worse.

Treatment usually begins with:

• Exercises to improve strength, flexibility and balance
• Weight loss, if needed, to improve pain, especially in your hips or knees
• Braces or shoe inserts (orthotics) that a health care provider fits for you

You can buy some pain relievers and arthritis creams without a prescription. They can be helpful, but it's best to talk to your provider about using them. If they don't help enough, your provider may prescribe injections (shots) into the joint or prescription pain relievers.

Complementary therapies may help some people. Massage can increase blood flow and bring warmth to the area. Some research shows that acupuncture may help relieve osteoarthritis pain. Simple things like heat and ice can help, too.

If none of these treatments help enough, surgery may be an option. You and your provider can decide if it's right for you.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases