A knee replacement should generally last for more than 20 years. However, most patients have different results. Roughly 90 percent of knee transplants last between 10 and 20 years. Knee replacement revision surgery is necessary for many patients to correct the problems caused by their knee replacement device. There are about 67,000 knee revision surgeries performed yearly in the United States. Many are done within a short amount of time after the initial surgery.
Undergoing a revision surgery is not only inconvenient but also carries a notable risk for the patient. Knee replacement revision surgery is typically more difficult to perform. Additionally, patients find that knee replacement revision surgery is often more painful and requires longer recovery time than the initial operation. Several knee replacement manufacturers face lawsuits from patients who experienced premature device failure and a need for knee replacement revision surgery.
Reasons for Knee Replacement Revision Surgery
There are several complications that can lead to revision surgery. Knee replacement revision surgery can be used to replace a failed knee replacement device. Additionally, knee replacement revision surgery can be used to correct injury caused to the knee from side effects of the device. Patients who require knee replacement revision surgery typically experience a similar list of symptoms. These symptoms include pain, swelling, stiffness, tenderness, and mobility problems.
Loosening and Wear
The method of fixation plays a large role in whether or not an implant loosens. Fixation can be achieved using cement to attach the implant and the bone. Some surgeons prefer to use non-cemented, or biologic, fixation processes. Over time, friction can compromise the integrity of the fixation.
This friction creates small particles of debris that collect around the knee joint. During aseptic, or non-infected, loosening, the fixation bond is destroyed due to the body’s attempt to break down and digest the debris. The patient’s bone may also be digested during this process. This condition is known as osteolysis.
In rare cases, the plastic or metal material of the knee replacement can allow a surface for bacteria to attach. These surfaces are inaccessible by antibiotics, which can lead to severe infection. The implant may loosen as a result of this. Even if the implant remains intact, the patient may experience infection symptoms that lead to knee replacement revision surgery. These symptoms include pain, swelling, and fluid collection.
Patients may experience peri-prosthetic fractures, or fractures that occur around the implant site. These fractures often interfere with the stability or fixation of the implant. If this occurs, the patient will typically require knee replacement revision surgery.
Knee Replacement Revision Surgery Process
Knee replacement revision surgery typically takes longer than the original knee replacement procedure. In many cases, knee replacement revision surgery takes roughly two to three hours. After the old components of a replacement device are removed, the surgery area is prepared for the revision implant. Implants for a revision surgery are different from the original, or “primary,” surgery implants. There are longer and thicker stems for extra support. Any damaged bone in the area must be removed and damage is usually extensive.
If the patient has lost a significant amount of bone, bone grafting may be sued to fill the voids. Bone grafts may be autograft or allograft. Autografts use bone from another part of the patient’s body. Allografts obtain the bone tissue from an individual who has donated to a bone bank. Wires, metal wedges, or screws can be used to provide additional strength to the bone.
Revision Surgery for Infection
If the knee replacement revision surgery was required to treat infection, other steps are typically taken. This may result in two separate knee replacement revision surgery procedures. In the first operation, the old device is removed. The surgeon implants a cement block that contains antibiotics. This is called an antibiotic-impregnated cement spacer. In another operation, a new knee replacement device is implanted. Intravenous antibiotics are typically administered to eliminate the infection.