A knee surgery is too generic a name to describe any one procedure. However, it is normally meant to mean either a partial or a total knee replacement. It needs to be understood that there are other surgical interventions carried out in the knee as well.

Components of a knee
Some of the common procedures are mending fractures in the bones in the joint or removing or repairing the patella and repairing ligament tears.

There are three bones in the knee joint, two of which are load bearing and another to give stability. These are the thigh bone, the Femur, the shin bone or the Tibia and the Patella or the knee cap. The fibula is a slender bone lying beside the Tibia on its outer side and affords stability. These bones are held tightly in position by a few ligament and tendons. The anterior cruciate ligament holds the Femur and Tibia together tightly in the front at the same time allowing movement. The posterior cruciate ligament does same in the rear. The two tendons, the medial collateral, and the lateral collateral lie on the inner and outer sides of the knee. The Patellar tendon, which is strictly a ligament, holds the patella close to the femur.

Types of knee surgeries

• Partial Knee Replacement is one of the major surgeries that is performed on the knee. This is necessitated when any one bone is damaged because of rheumatoid arthritis or osteoarthritis. Rheumatoid arthritis is an autoimmune disease in which the body’s immune system attacks and destroys the lining of the joint, the synovial membrane. The prolonged condition leads to deterioration of the joint itself. In osteoarthritis, the cartilage that lines the articular surface of the bones with glassy low friction surface is damaged. The damage can be only on one bone, so in that case, only the damaged portion of that bone has chipped away and the joint replaced with metal or polyethylene inserts.
• Total Knee Replacement or arthroplasty is when the damage is extensive and both the bones are replaced. Under general anesthesia, the surgeon opens the joint and remove the damaged portions of both the bones Femur, the Tibia and the Patella, and replaces them with metal or polyethylene artificial joints and then the joint is fixed to the bones. Postoperative physiotherapy is essential and is quite painful.

These surgeries are not without their drawbacks. Besides the general risks of anesthesia, these surgeries can also cause embolisms, infections and in some cases persistent pain. Although a good, well-fitted joint serves well for over 20-25 years, premature failures are known to have happened.