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Common Questions About Knee Replacement

What happens during knee replacement surgery?

Knee replacement surgery replaces the worn out surface of the joint. The knee is made up of the inside (medial) and the outside (lateral) compartments, as well as the joint between the kneecap (patella) and the femur. During your surgery, the surgeon will open the knee and make precise cuts on the bones. Bone spurs, called osteophytes, are removed. The implants will be precisely sized to fit your knee. The surgeon then "trials" implants to make sure that your knee is correctly aligned and that it bends and straightens. The real implants are then placed and the knee is closed.

What are the types of implants?

There are many designs of knee replacement made by different companies. These designs are relatively similar. A metal cap is placed on the end of the femur and the tibia. In between is a plastic liner that locks onto the tibial component. Knee replacement may be fixed to the bone with bone center or with a rough surface that allows for bony ingrowth. Ask your surgeon for details about the exact implant to be used.

When can a partial knee replacement be done?

A small number of patients have arthritis in only one area of the knee. These patients may be candidates for a partial knee replacements. Partial knee replacements can be done through smaller incisions. Ask your doctor if you are a candidate for partial knee replacement.

What "approach" is best for me?

Knee replacement is performed through an incision on the front of your knee. Minimally invasive approaches are now available; however, the benefits of this approach are unclear. Smaller incisions make the correct placement of the knee replacement implant very difficult and may increase the risk of leaving excess bone cement in the joint.

What results can I expect from my new knee?

We believe that 90 to 95 percent of patients have good to excellent results, even at ten years post knee replacement.

While knee replacement gives excellent pain relief, it does not give you a normal knee. Many patients are pain-free, but some may still have occasional aches and an awareness that it's not their "own" joint. Most patients can get back to activities; however, we do not recommend high impact activities or running after knee replacement. We do recommend golf, walking, weight lifting, dancing, bicycling or swimming. More dangerous activities, such as horseback riding, skiing and waterskiing are possible, but do place your joint at some risks. A fall may cause the knee to dislocate or the bone to break around the implant. These activites are not recommended unless you already are at an advanced level.

Many patients find that kneeling is painful after knee replacement surgery. Do not forcefully kneel or jump onto your knee. The knee cap (or patella) is thinner due to the replacement and can fracture. Gentle kneeling is fine as long as it is not too painful. For example, use a pad for gardening and practice before kneeling in church.

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