What is Knee Osteoarthritis?
Osteoarthritis (OA) is a common problem for many people after middle age. OA is sometimes referred to as degenerative, or wear and tear, arthritis. OA commonly affects the knee joint. In fact, knee OA is the most common cause of disability in the United States.
In the past, people were led to believe that nothing could be done for their problem. Now doctors have many ways to treat knee OA so patients have less pain, better movement, and enhanced quality of life.
This article will help you understand how OA develops, how OA of the knee causes problems, and how doctors treat the condition.
Which parts of the knee are affected by Knee Osteoarthritis?
The main problem in OA is degeneration of the articular cartilage. Articular cartilage is the smooth lining that covers the ends of the leg bones where they meet to form the knee joint. The cartilage gives the joint freedom of movement by decreasing friction. The layer of bone just below the articular cartilage is called subchondral bone.
When the articular cartilage degenerates or wears away, the bone underneath is uncovered and rubs against bone. Small outgrowths called bone spurs or osteophytes may form in the joint.
How does Knee Osteoarthritis develop?
OA of the knee can be caused by a knee injury earlier in life. It can also come from years of repeated strain on the knee. Fractures of the joint surfaces, ligament tears, and meniscal injuries can all cause abnormal movement and alignment, leading to wear and tear on the joint surfaces.
Not all cases of knee OA are related to a prior injury, however. Scientists believe genetics makes some people prone to developing degenerative arthritis. Obesity is linked to knee OA. Losing only 10 pounds can reduce the risk of future knee OA by 50 percent.