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How Osteoarthritis Affects Your Knee
Healthy Knee
In a healthy joint, a rubbery tissue called cartilage cushions the ends of the bones at contact points. A thin, smooth tissue called the synovial membrane covers the other surfaces and releases a fluid that lubricates the knee.
Thigh Bone
The knee is one of the largest joints in the body, and one of the most complex. It is formed by the shin bone (tibia), the thigh bone (femur), and the knee cap (patella).
Knee With Osteoarthritis
Osteoarthritis in the knee begins with the gradual deterioration of cartilage. Without the protective cartilage, the bones begin to rub together, causing pain, loss of mobility, and deformity.
Eroded Cartilage
Cartilage becomes damaged and gradually wears away, allowing bone surfaces to rub together.
Reviewed by Brunilda Nazario, MD on December 02, 2008
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The American Academy Of Orthopedic Surgeons says approximately 300,000 total knee replacements are performed each year in the US. Surgeons have a new tool to help them rebuild knees with more flexibility.
"Fowl" Shot for Osteoarthritis
