Revision Knee Surgery

Revision knee surgery is the replacement of implants in someone who had received a total knee replacement before. This surgery is sometimes called a “reoperation.” 

Overview

While knee implants are designed to last a long time, that doesn’t mean that they will last forever. For around 85% – 90% of people who receive a total knee replacement, the implants will last around 15 to 20 years. This means that people who have a knee replacement done at a younger age might end up needing a second surgery at some point to clean the surfaces and refixate the implants. Other people might need their implants completely replaced with new ones.

Causes of a Revision Knee Surgery

Elderly patients who get a knee replacement might never need to replace their implant. However, these revision procedures are common in younger patients who continue to maintain an active lifestyle. The need for a revision knee surgery arises when someone’s prosthetic knee implant fails. This could be because of injury, wear, or an infection around the implant.

• Wear and Tear: This is the loosening or breakage of prosthesis components because of friction over time. While implants are fixed at the initial surgery, they could become loose as time goes on. When it comes loose, patients could experience pain, a change in alignment, and instability.
• Instability: Sometimes, the soft tissues around the knee aren’t able to provide the stability needed for adequate knee function. Patients might notice pain or a feeling of the knee giving away to signal their instability.
• Stiffness: If patients have excessive scar tissue build up around the knee, it could prevent the knee joint from functioning properly, leaving it feeling stiff.
• Infection: The risk of infection from a knee replacement surgery is less than 1%, but when it does occur, a knee revision is needed.

Symptoms of Knee Replacement Failure

People who might need revision knee surgery most commonly experience symptoms like pain, decrease in knee function, instability, swelling, or stiffness. Persistent pain and swelling of the knee joint could indicate loosening, wear, or infection. The decrease in knee function could become noticeable with a limp, stiffness, or instability.

The Procedure

In revision knee surgery, the failed knee prosthesis is replaced with a new one. Some might think of it as the replacement of a knee replacement.

Incision Made

After being administered anesthesia, a vertical incision will be made in the knee. The incision will be long enough to expose the kneecap and the ligaments connecting it to the tibia and fibula. Once the incision has been made, the kneecap and tendons will be moved to the side to allow for viewing of the knee joint. 

Once in, your surgeon will inspect the soft tissues of the knee to ensure there is no infection. They will also assess the metal and/or plastic parts of the original implant to determine the parts that are worn, loose, or out of position.

Removal and Replacement of Implant

First, the old component will be removed from the femur. Then the femur will be reshaped to prepare for the new component, if necessary. When the femur is ready, the new component will be attached using bone cement. 

Then, the old component will be removed from the tibia. The tibia will also be reshaped and its center will be hollowed to allow for the new component. When removing the old implant, sometimes the surgeon may notice significant bone loss around the knee. Metal augments and or bone grafts might need to be added to make up for these deficits. Once that has been taken care of, the new tibia component will be secured to the tibia using bone cement.

Attachment of Plastic Plate

When the tibia component has been secured, a plastic plate will be attached to it. This will support the body’s weight and help the femur to move over the tibia.

End of Procedure

Finally, the rear of the patella will be resurfaced and a new plastic component will be attached with the use of bone cement. Then, the patella and the tendons will be placed back in their normal position before the incision gets closed.