Osteoarthritis

Osteoarthritis is the most common form of arthritis. In fact, more than 75 percent of people older than fifty-five show the joint deformations of osteoarthritis on X-rays. But most of these people have no symptoms. However, for those who do have symptoms, osteoarthritis can become a crippling disease. More than 20 million Americans receive medical attention for osteoarthritis each year.

Osteoarthritis is most common in the small joints of the hands, the spine, the knees, the hips, ankles and feet. Some people have symptoms of OA in just one joint, while others have it in several joints. Osteoarthritis primarily affects the articular cartilage that covers the ends of the bones in most joints.

What is Osteoarthritis?

Osteoarthritis (OA) is essentially a "wear-and-tear" disorder. In typical cases, symptoms appear after the age of 50, and it is therefore most common in those parts of the world where people live the longest. Over the years, the cartilage that protects the ends of the bones in joints becomes damaged or worn away. The disease is progressive.

In the early stages of osteoarthritis, the cartilage actually becomes thicker as your body tries to repair the damage. The repaired areas are more brittle than the original cartilage, and these brittle areas begin to wear away and become thin. They may even wear away entirely. This eventually leads to a condition called eburnation, in which the bones become thick and polished as they rub together.

Osteoarthritis is not just a disease of the cartilage. The damage to the cartilage seems to start a sort of chain reaction that involves all the parts of the joint. Bone spurs, or outgrowths, often begin to form around the edges of the joint. The joint capsule (the watertight sack around the joint) can become thickened and lose its stretch. The synovial membrane that lines the inside of the joint capsule may become inflamed (swollen, red, hot, and painful), and crystals may form in the synovial fluid. The tendons and ligaments around the joint can also become inflamed.

Even the muscles around the joint can lose their strength. This usually occurs as a result of under-use of the muscles due to pain in the joint. When something hurts, we subconsciously change the way we use the joint to avoid the pain. This causes the muscles to become weakened. Because cartilage itself does not have nerves to feel pain, the pain of osteoarthritis comes from these other changes in and around the joint.

Most cases of osteoarthritis can be handled by rest and medication. When pain cannot be relieved and joint function cannot be maintained, your doctor may recommend surgery to replace the affected joints.