Knee osteoarthritis is the most common form of osteoarthritis. In the first stage, symptoms are mild, but by the fourth, a person may need surgery.

Osteoarthritis (OA) of the knee affects the bones, the cartilage, and the synovium in the knee joint.

Cartilage is a slippery tissue that provides a smooth surface for joint motion and acts as a cushion between the bones.

Synovium is soft, and it lines the joints. It produces fluid, called synovial fluid, for lubrication, and it supplies nutrients and oxygen to the cartilage.

As these functions break down, they no longer protect the bones of the knee joint, and bone damage occurs.

Total knee replacement is one of the most successful procedures in all of medicine. In the vast majority of cases, it enables people to live richer, more active lives free of chronic knee pain.

• Over time, however, a knee replacement may fail for a variety of reasons such as implant wear and loosening may require a revision procedure to replace the original components. When this occurs, your knee can become painful and swollen. It may also feel stiff or unstable, making it difficult to perform your everyday activities.
• In this case, your doctor may recommend that you have a second surgery—revision total knee replacement. In this procedure, your doctor removes some or all of the parts of the original prosthesis and replaces them with new ones.
• It is a longer, more complex procedure that requires extensive planning, and specialized implants and tools to achieve a good result.