In the beginning stages of osteoarthritis you may have no symptoms, but signs of the disease may be seen on an x-ray. Since the knee is one joint in your body that bears a lot of weight, we've used this as an example to explain the stages by which the breakdown of cartilage occurs in this progressive disease.

Healthy

Stage I - Mild

Stage II - Mild to Moderate

Stage III - Moderate

Stage IV - Severe

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A healthy knee has a cushiony substance called cartilage on the ends of the bones.

Cartilage is smooth and protects the ends of the bones from rubbing against each other and reduces friction.

Inside your joint, there is a space between the cartilage of one bone and the cartilage of another. This space holds a fluid called synovial fluid.

When you have osteoarthritis of the knee, your knee changes a little at a time.

These changes can cause irritation, discomfort, and/or pain.

The surface of the cartilage begins to break down.

Unhealthy cartilage is more easily damaged by everyday wear and tear or injury.

In osteoarthritis, synovial fluid may lose its ability to adequately lubricate and cushion the joint.

Large sections of cartilage may wear away over time.

Bony growths, or spurs, may form on the edges of bones.

Areas of cartilage may totally wear away, leaving bone rubbing against bone.

The symptoms of osteoarthritis are treatable, especially in the early stages of the disease. If you have pain or stiffness in a joint, contact your doctor to be evaluated for osteoarthritis and other conditions. There are different therapies available to help reduce or eliminate the pain associated with osteoarthritis. Your doctor can help choose a treatment that's right for you.