Revision Knee Replacement (Arthroplasty)
Enhancing Stability and Comfort Following Previous Knee Surgery
If you’ve had a knee replacement but are experiencing ongoing pain, stiffness, or difficulty moving, a revision knee replacement may help improve your comfort and mobility.
This procedure involves replacing worn, or problematic components of your existing implant or, in some cases, it may also include rebuilding damaged bone or soft tissues using bone grafts, specialised implants, or supportive materials to restore stability.
It’s important to note though that revision knee replacement is a complex surgical procedure that requires a skilled and experienced orthopaedic surgeon.
Dr Antony Liddell will assess your individual situation and recommend the best approach to help you regain confidence in your movement.
Common reasons a knee replacement may stop working properly
While knee replacements are designed to improve mobility and relieve pain, some implants may not function as expected over time. Several factors can contribute to implant failure, leading to discomfort, instability, or reduced function:
Knee implants are built to last, but over time, the materials—particularly the polyethylene (plastic) components—can gradually wear down. This can lead to tiny particles being released into the joint, causing inflammation and potential loosening of the implant, which may result in pain and reduced mobility.
Implant loosening is one of the most common reasons for revision surgery. This occurs when the bond between the implant and the bone weakens, which may be due to natural bone changes, wear, or insufficient initial fixation. Loosening can cause instability, discomfort, and difficulty walking.
Infection around a knee implant can develop soon after surgery or years later. If bacteria enter the joint, they can damage surrounding tissue and bone, leading to pain, swelling, and implant failure. In these cases, revision surgery is often required to remove the infected implant, treat the infection, and replace the knee replacement.
If the components of the knee implant are not positioned correctly during the initial surgery, uneven pressure may be placed on certain areas of the joint. This can lead to pain, restricted movement, and premature implant wear, sometimes requiring revision surgery to correct alignment issues.
A fracture near the knee implant, known as a periprosthetic fracture, can compromise the stability of the replacement. This may occur due to a fall, an accident, or weakened bone around the implant. Depending on the severity, surgery may be required to repair the fracture or replace the implant.
Excessive scar tissue can develop around the knee after surgery, leading to stiffness and restricted movement. In severe cases, this may interfere with the function of the implant and require a procedure to remove the scar tissue and restore mobility.
Although rare, some individuals may experience an allergic reaction to the metal components in a knee implant. This can lead to pain, swelling, and persistent inflammation, potentially contributing to implant failure.
Your lifestyle, overall health, and activity levels can influence how long your knee replacement lasts. High-impact activities, obesity, or conditions like osteoporosis can increase stress on the implant, potentially leading to complications over time.
If you’re experiencing ongoing pain, swelling, or difficulty with your knee replacement, Dr Antony Liddell can assess your situation and discuss possible treatment options, including revision knee replacement if necessary.
What’s replaced during revision knee surgery
If you’re considering a revision knee replacement, you may be wondering what goes into the new implant and how it can help restore your movement and comfort. Modern knee implants are designed to improve stability, durability, and flexibility, helping you regain confidence in your knee function.
Dr Antony Liddell carefully selects each component of your implant based on your unique anatomy and the challenges of your revision surgery. Below are the key parts of a revision knee replacement and how they contribute to better movement and long-term success.
The femoral component replaces the damaged or worn-out part of your thighbone (femur) and helps your knee move smoothly. It is made from strong materials like titanium or cobalt-chromium, designed to last for many years. This component is carefully shaped to match the natural contours of your femur while preserving as much healthy bone as possible.
If your kneecap (patella) is worn down, resurfacing it with a polyethylene (plastic) component can help reduce pain and improve how your knee moves. This part of the implant improves the connection between the patella and the femur, helping to prevent friction and making everyday activities like walking and climbing stairs feel more natural.
The tibial base plate sits on top of your shinbone (tibia) and supports the knee implant. It can be cemented or mechanically fixed to ensure a secure hold. This component is important because it provides a strong foundation for the knee replacement, allowing for both immediate stability and long-term durability.
The polyethylene insert acts as a shock absorber between the metal components of your knee implant. It cushions movement and helps your knee bend and straighten smoothly. The insert can be adjusted in thickness to fine-tune alignment and improve stability, which is especially important in revision knee replacement.
The tibial inlay helps your knee move naturally while maintaining stability. It comes in two designs:
- Fixed-bearing inlays – These remain in place, providing extra stability for those with ligament weakness.
- Mobile-bearing inlays – These allow slight movement, helping distribute pressure evenly and reduce long-term wear on the implant.
Offsets help customise the position of your implant to better match your natural knee anatomy.
- Tibial offsets fine-tune how the tibial component sits on your shinbone, preventing overhang or soft tissue irritation.
- Femoral offsets adjust the position of the femoral component to optimise joint alignment and comfort.
These small adjustments can make a big difference in how your knee replacement feels and functions.
If your bone quality has changed due to previous surgeries or osteoporosis, extension stems may be added to your implant. These long metal rods extend into your bone, giving the implant extra support and helping it stay securely in place.
Intramedullary stems work similarly to extension stems but are anchored deeper into your bone to provide additional reinforcement. This is particularly important in revision knee surgery, where extra stability is often needed.
If you have bone loss from previous surgeries or arthritis, metal augments (fillers) can be used to rebuild the shape of your femur. These augments help restore proper joint alignment and improve knee balance, making movement feel more natural.
In some cases, tibial wedges or blocks are used to fill bone gaps in the shinbone (tibia). This ensures your implant has a stable and secure fit, reducing the risk of implant loosening.
If your knee ligaments are weak or have been damaged, special CCK components may be used. These extra supportive implants help keep your knee stable while still allowing for some natural movement.
In cases where your knee joint is severely unstable, a rotating hinge knee implant may be recommended. This implant mimics natural knee movement while keeping the joint from moving in ways it shouldn’t. It provides maximum stability, which is essential for maintaining balance and strength after revision surgery.
Every revision knee replacement is unique, and the implant components are carefully selected based on your individual needs. Dr Antony Liddell uses advanced imaging and surgical planning to determine the best combination of implants to restore your knee function, improve comfort, and enhance long-term success.
If you’re experiencing pain, instability, or difficulty moving after a previous knee replacement, Dr Liddell can assess your situation and discuss whether revision surgery is the right option for you.
How revision knee replacement surgery is performed
If your knee replacement is causing pain, instability, or other complications, revision knee surgery may be needed to restore comfort and movement. The procedure is more complex than a primary knee replacement and requires careful planning to address issues such as implant loosening, wear, bone loss, or infection.
Depending on your specific needs, Dr Antony Liddell will determine whether a one-stage or two-stage revision is the best approach for you.
For many patients, one-stage revision is an effective way to replace a failing implant in a single procedure.
- The old implant is carefully removed.
- ✔ The surrounding bone and tissues are thoroughly cleaned.
- ✔ A new implant is placed to restore function and stability.
This approach is usually recommended when there is no infection or when an infection can be effectively treated during the surgery itself. Recovery from a one-stage revision is typically similar to a standard knee replacement, though rehabilitation may take longer due to the complexity of the procedure.
If an infection is present around your knee replacement, a two-stage revision is often the best option. This approach is performed in two separate surgeries to ensure the infection is completely treated before a new implant is placed.
- Stage One – The infected implant is removed, and a temporary spacer is inserted into the knee. This spacer helps maintain joint space and allows movement while delivering antibiotics to clear the infection.
- Stage Two – Once the infection is fully resolved, a second surgery is performed to remove the spacer and implant the new knee replacement.
Although a two-stage revision takes longer, it is considered the most reliable method for treating implant-related infections and improving long-term success.
Because revision surgery is more complex than a primary knee replacement, the procedure usually takes two to three hours per surgery. Factors such as bone loss, scar tissue, or infection may extend the surgical time.
Dr Antony Liddell will carefully assess your condition and discuss the best surgical approach for your specific needs, ensuring the best possible outcome for your knee health and mobility.
A personalised plan for your revision knee surgery
Every revision knee replacement is different, and the level of complexity can vary. Some procedures are straightforward, while others require advanced techniques to address issues like implant loosening, bone loss, or infection.
During your consultation, Dr Antony Liddell will take a detailed medical history, perform a thorough examination, and review your imaging scans to develop a surgical plan tailored specifically to you. His goal is to restore stability, reduce pain, and improve knee function, so you can move more comfortably again.