Total knee replacement surgery (also known as knee arthroplasty) is one of the most life-changing procedures in orthopedic medicine. For patients with severe knee damage, knee replacement can reduce pain and restore normal movement to the joint, immensely improving their quality of life. Hundreds of thousands of knee replacements are performed each year in the United States.
Although surgical materials and techniques grow continually more advanced, knee replacement does not always provide permanent results. A knee replacement may fail for a variety of reasons, causing the knee to become swollen, painful, stiff and unstable. These changes can make it difficult to perform everyday activities once again, and a doctor may recommend a second surgery — revision knee replacement.
A knee implant consists of several components that resemble a natural knee joint in both structure and movement. A metal femoral component attaches to the lower end of the femur (thighbone). A tibial component connects to the end of the tibia (shinbone). A patellar component replicates the shape of the patella (kneecap). A plastic spacer fits between the tibial and femoral components to provide a smooth, gliding surface for fluid movement of the joint.
Revision knee replacement surgery takes place when a knee replacement fails. Depending on the extent of the revision surgery, some or all of the implant components will be replaced.
Revision surgery is different from primary knee replacement. It is a longer and more intricate procedure that requires specialized tools, careful planning and mastery of advanced surgical techniques to achieve a good result.
In the simplest cases, one of the three components of the prosthesis must be removed and replaced. In more complex cases, two or all three components require revision. In the most complex cases, when there is damaged or missing bone around the implant, it must be rebuilt with bone grafts or augments (metal pieces that replace missing bone).
Weakened bone may make it difficult for the surgeon to use standard knee implants for revision knee replacement. These cases require implants with longer, thicker stems that extend deeper into the bone for additional support and stability.
Compared to the primary knee replacement, a revision knee replacement has a higher risk of complications, especially if there is extensive scarring from the initial procedure. Additionally, a revision procedure doesn’t guarantee the same longevity as the initial knee replacement.
Although many revision knee surgery patients have favorable outcomes, it’s important to understand the complexities and limitations of revision procedures before proceeding.
Artificial knees are designed to last a long time, but they do not last forever. Most knee replacements last a decade or two, some longer. A small percentage of patients (approximately 1% to 2%) end up requiring revision knee replacement surgery within a few years of their initial knee surgery. A study presented at the 2018 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) estimated that total knee replacements will grow to 1.28 million procedures per year by 2030. The study estimated that revision knee replacements will reach 120,000 procedures in the same year.
As new materials and surgical techniques are developed, physicians hope to provide even longer-lasting knee replacements.
Young and active patients have a higher rate of knee replacement revision than older, less active patients because they put more stress on their implant over time. People who are young at the time of their initial knee replacement may also simply “outlive” the life expectancy of their artificial knee.
Obesity is associated with a higher incidence of wear and loosening due to the increased stress placed on the prosthesis. People who are overweight are also more prone to infections because of their elevated risk of poor wound healing.
A person’s medical history is another factor to consider. Individuals with previous knee surgeries are at higher risk for infection and implant failure.
When an artificial knee stops functioning properly, revision surgery may be necessary to replace the defective components. The reasons a knee replacement might fail include:
Patients who demonstrate symptoms of these conditions should see an orthopedic specialist who can identify the cause of the issue and determine whether revision surgery is necessary.
A failed knee replacement is usually indicated by one or more of the following signs and symptoms:
Many people pursue revision knee replacement because they are in significant pain. While pain itself can be a problem, revision surgery should not be performed without understanding the underlying reason why the pain is occurring. An operation for pain without an identified cause and a clear plan to address it is unlikely to yield optimal results.
Revision knee replacement is typically a longer, more complex procedure than initial knee replacement. It has a greater risk of complications and requires more extensive planning and surgical expertise to achieve a good result. It is not a procedure to be taken lightly, but when performed on the right candidate by an experienced surgeon, it can be highly rewarding.
Revision knee replacement is generally recommended for patients who are in relatively good health overall, but who are experiencing complications from their original surgery that are preventing them from leading a fulfilling life. Patients who are young when they receive their implant are more likely to require revision surgery in the future, as the artificial joint tends to wear out over time.
Before undergoing surgery, you will visit the Orthopaedic Institute of Ohio for a consultation. Your OIO physician will perform a complete physical examination to ensure you are healthy enough for surgery and the recovery process. They will likely order imaging tests, such as an x-ray or MRI, to learn more about the condition of your knee and the prosthesis.
If infection is suspected, your doctor may order a blood test or aspirate your knee (removing joint fluid with a needle).
You can simplify the recovery process by planning ahead. Arrange for caretakers to drive you home from the surgery and help with tasks like cooking, shopping and doing laundry while your mobility is limited. It can be helpful to set up a designated “recovery area” in your home where you have easy access to necessities and entertainment.
Like primary knee replacement surgery, this procedure is performed under general or regional anesthesia. Incisions are made in the same location as the initial surgery to minimize postoperative scarring. However, the revision incision may be longer than the original to allow the old components to be removed.
Once the incision is made, your surgeon will move the kneecap and tendons aside to see your knee joint and examine the area for infection and signs of damage. Your surgeon will assess the components of the implant to determine if any pieces have worn down, come loose or shifted out of position. The outcome of this assessment will dictate the specific techniques used in your procedure. A revision knee replacement must be tailored precisely to the individual patient’s needs to ensure the highest chance of success.
If necessary, your surgeon will remove the original prosthesis, paying careful attention to preserving as much bone as possible. Any cement used to attach the prosthesis to the bone will be removed as well. Your surgeon can then prepare the bone surfaces for the revision implant, which may involve bone grafts or metal augments.
Finally, your surgeon will place the revision implant, repair any soft tissues that are damaged and test the motion of the joint. You will be moved to our recovery room when the surgery is complete, where you will be monitored for several hours while waking from anesthesia.
Although recovery after revision knee replacement is usually slower than recovery after the initial surgery, the care you receive and the postoperative instructions you will be asked to follow are similar.
You will be monitored for a day or two in the hospital before returning home to recover in familiar surroundings. Medications will be used to reduce the risk of blood clots and infection. You may also be prescribed medications for short-term pain relief after surgery. As soon as your pain starts to improve, transition from prescription pain medications to over-the-counter pain relievers.
You may require a cane, walker or crutches until you are comfortable enough to walk without assistance. Because your mobility will be limited, you may need some help at home from friends, family or a caregiver for several days to several weeks after your surgery. Follow your surgeon’s instructions carefully to optimize wound healing and reduce your risk of developing complications.
A physical therapist will give you exercises to restore strength and range of motion to your knee. It’s important to stand and walk as quickly as possible to help the bone bond properly with the implant. Physical therapy may be initiated as soon as one day after the procedure and usually continues for three months. The more closely you adhere to your rehabilitation regimen, the sooner you will be able to resume regular activities.
Most people who undergo knee revision procedures can expect to have good results. However, complete pain relief and restoration of joint function are not always possible. It’s also important to note that a revision knee replacement is not expected to have the same lifespan as the initial replacement. While initial knee replacements can last up to 20 years, revision knee surgeries typically last about 10.
Knee replacement enables patients to live richer and more active lives free of chronic pain. Over time, however, a knee replacement may require revision surgery to continue providing pain relief, stability and improved range of motion. Most patients who have revision knee replacement surgery experience positive long-term outcomes. To learn more or find out if you are a candidate for this procedure, contact the Orthopaedic Institute of Ohio in Lima today at (419) 222-6622.