Need To Know About Knee Replacement Revision Surgery

Knee implants have tremendously evolved in the last decade, thanks to advanced on technical and manufacturing techniques. Now the knee implants last for several years. However, there is still a scope left for the prosthetic to wear out or break a few years after implantation. In such cases, a knee replacement revision surgery is warranted. A knee revision surgery involves a partial or complete replacement of the prosthesis that was originally placed during the knee replacement surgery.

However, this is not necessary in all cases. For example, some candidates may just require cleaning of the prosthesis and the underlying bone. Whereas in others, the doctors may replace just one or two components during the surgery. A knee replacement may fail for many reasons. This may result in extreme pain and swelling. People may feel extreme stiffness and be unable to move around when the implants fail. In such cases, the doctors recommend a second surgery, which is the revision procedure.

The main aim of both knee replacement and revision surgery is to relieve pain and inflammation and improve the quality of life. However, the approach to achieve the objective is completely different. This article explores some of the important things that you may need to know about knee replacement revision surgery.

Criteria for Revision Knee Replacement: Why is It Needed?

In more than 80 percent of the total knee replacement cases, the knee implants last for at least 15 years. Therefore, they may last for life in the case of the elderly. However, younger candidates are at an increased risk of implant failure. Such individuals may eventually require revision surgery when the implants fail. There is some amount of bone loss in the total knee replacement procedure. This is the reason why doctors may not be able to use the regular implants that they used in the original procedure. Sometimes, they decide to use special implants with thicker stems that are fitted deep into the bone. The following are some of the reasons why the doctors may recommend a revision knee replacement:

Infection

Infection is one of the potential complications of knee replacement. This complication arises while you are still at the hospital or may even manifest after discharge. In some patients, an infection occurs years after the surgery. Depending on the extent and degree of infection and the type of bacteria present, the doctors may conduct:

Debridement: In this case, the metal components are left as is. Only the plastic spacer is replaced and the bacteria is washed off.
Staged surgery: In this case, the implant is completely removed. This takes place in two stages. In the first stage, a spacer treated with antibiotics is left in the void after removing the implant for several weeks. After the infection is clear, the surgeons insert a new prosthesis.

Implant Loosening

The prosthesis should remain firmly fixed to the bone. However, over a period of time, the implant may loosen from the bone, which may result in knee pain. The implant may loosen because of several reasons. Excessive weight, wear of the plastic spacer, and high-impact activities are some of the reasons. Additionally, younger patients may sometimes outlive the life of the implant, which may ultimately loose up after 15 to 20 years. Implant loosening may also occur because of osteolysis, which is an immune response to the bone that surrounds the implant. The specialist conducts a revision surgery in such cases.

Mechanical Failure

The knee implant may fail when it does not produces results as expected. This may happen because of improper placement of the implant during the surgery and poor choice of implant. It may also occur because of fabrication issues and defect in the implant. The causes can be broadly categorized into surgical, material-related, and idiosyncratic. Surgical issues include issues related to the technique, judgment, and surgery-related infections. Material-related issues include chemistry, engineering design, and structural metallurgy. Idiosyncratic issues include rejection of implant due to specific conditions such as pain, implant loosening, and sinus tract infection. The implant may sometimes dislocate from its original location as well. In such cases, doctors also conduct a revision surgery.

Fracture

A fracture may take place in the bone surrounding the prosthesis. These usually result because of trauma, accident, or a fall. In such cases, the doctors conduct a revision surgery. If the bone is completely damaged because of injury or conditions such as osteoporosis, the surgeon may decide to use a bigger revision component. In other cases, the surgeons conduct partial revision.

Instability

The knee may become unstable after getting implants when the ligaments surrounding the joint are no longer healthy. The prosthesis work with the original ligaments. Any damage to these ligaments may eventually affect the prosthesis, increasing the need for revision surgery. The instability may eventually lead to pain and affect the quality of life.

Stiffness

Sometimes, excessive scar tissues may build up around the knee. This may affect the range of motion and thus, affect the ability to perform daily activities. In the case of scar tissue build-up, the doctors may try to manipulate it by bending the knee aggressively. The surgeon advises a revision surgery when the scar tissue is extensive or if the range of motion is not as desired.

Why is Revision Surgery Tougher than the Original Knee Replacement?

Revision surgeries are more susceptible to complications than the original knee replacement surgery. Additionally, the accumulated scar tissue, mechanical breakdown, and trauma can further complicate things. Revision surgery is more complicated than knee replacement because it involves the complete removal of the original implant. There are huge chances that the implant may have already become attached to the bone by the time a revision surgery is needed. This can further complicate the situation as there may be significant bone loss due to the removal of the implant. Further, the patient may experience specific symptoms such as: