Osteoarthritis is the most common chronic joint condition. A joint is where two bones come together. The ends of these bones are covered with protective tissue called cartilage. With OA, this cartilage breaks down, causing the bones within the joint to rub together. This can cause pain, stiffness, and other symptoms. OA occurs most often in older people, although it can occur in adults of any age. OA is also called degenerative joint disease, degenerative arthritis, and wear-and-tear arthritis.

A leading cause of disability, OA affects more than 30 million men and women in the United States. Here’s everything you need to know about OA, from treatment to prevention and more. OA is caused by joint damage. This damage can accumulate over time, which is why age is one of the main causes of the joint damage leading to osteoarthritis. The older you are, the more wear and tear you’ve had on your joints. Other causes of joint damage include past injury, such as:

• torn cartilage
• dislocated joints
• ligament injuries

Cartilage is a tough, rubbery substance that’s flexible and softer than bone. Its job is to protect the ends of bones within a joint and allow them to move easily against each other. When cartilage breaks down, these bone surfaces become pitted and rough. This can cause pain within the joint, and irritation in surrounding tissues. Damaged cartilage can’t repair itself. This is because cartilage doesn’t contain any blood vessels.

People with RA have immune systems that mistake the soft lining around joints to be a threat to the body, causing it to attack that area. This soft lining, which includes the synovial fluid, is called the synovium. As the immune system launches its assault, fluid buildup within the joint occurs, causing stiffness, pain, swelling, and inflammation.

If you’re not sure which form of arthritis you have, your best bet is to talk to your doctor. But you can also do your own research