What is Knee Arthritis?
The joint surface is covered by a smooth articular surface that allows pain-free movement in the joint. Arthritis is a general term covering numerous conditions where the joint surface or cartilage wears out. This surface can wear out for several reasons; often the definite cause is not known.
Arthritis often affects the knee joint. When the articular cartilage wears out, the bone ends rub on one another and cause pain. The most common type of arthritis is osteoarthritis. It occurs with aging and use.
What are the Causes of Knee Arthritis?
There are numerous conditions that can cause arthritis but often the exact cause is never known. In general, but not always, it affects people as they get older (osteoarthritis). Other causes include:
- Trauma (fracture)
- Increased stress such as overuse and overweight
- Infection of the bone
- Connective tissue disorders
- Inactive lifestyle and obesity (overweight). Your weight is the single most important link between diet and arthritis, as being overweight puts an additional burden on your hips, knees, ankles, and feet.
- Inflammation (rheumatoid arthritis)
What are the Symptoms of Knee Arthritis?
Knee arthritis causes pain and decreased mobility of the knee joint. The cartilage lining is thinner than normal or completely absent. In the arthritic knee, there is an absent joint space that shows on X-ray. In the normal knee, there is a normal joint space.
The capsule of the arthritic knee is swollen. The degree of cartilage damage and inflammation varies with the type and stage of arthritis. Bone spurs or excessive bone can also build up around the edges of the joint. The combinations of these factors make the arthritic knee stiff and limit activities due to pain or fatigue.