Robotic knee replacement surgery
On average, 1 in 5 patients with a total knee replacement are unhappy with the result of their operation.
Why consider a robotic knee replacement?
It allows your surgeon to plan your knee replacement and execute that plan with accuracy.
Pressed for time? View the infographic for a summary.
Total knee replacements are successful operations that are designed to relieve pain in patients with knee arthritis. The technology behind knee replacements has been evolving since the first modern knee replacement, which was performed in 1968. Despite the use of modern knee replacement components, data shows that 1 in 5 patients are dissatisfied with the outcome after having a knee replacement. Surgical techniques and knee replacement prostheses are constantly being refined in an effort to improve patient satisfaction.
A conventional knee replacement is performed using jigs that assist the surgeon to make the bony cuts to allow implantation of the knee replacement prosthesis. The jigs are positioned using anatomical landmarks within the knee. Even with inexperienced hands, there is a degree of variability with the final implant position.
Computer navigation was designed to reduce this variability by using trackers attached to the patient that relay information to a computer. The trackers allow more accurate placement of the jig, which reduces variability. Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOA-NJRR) shows that patients younger than 65 whose knee replacement was performed using computer navigation had a lower revision rate.
Patient-specific jigs are another form of technology designed to improve accuracy. Preoperative imaging of the patient’s knee is used to generate a virtual model that will allow a patient-specific jig to be manufactured. The jig is applied to the patient’s knee, and the surgeon performs the bony cuts using a standard saw. Even though the jigs used are custom-made, the implant itself is not custom-made for the patient, and there are still instances where the jig may not fit accurately onto the patient’s knee intraoperatively. In these cases, the surgeon may need to revert to a conventional technique to make accurate bony cuts.
How is a robotic knee replacement performed?
Robotic-assisted knee replacements have improved on computer navigated technology.
Steps involved:
Preoperative imaging of the knee is used to create a virtual model.
The model is used to plan the knee replacement implant size and positioning.
During the operation, anatomical landmarks within the patient’s knee are used to verify the positioning suggested by the virtual model prior to bony resection.
The surgeon performs the bony cuts with the assistance of the robot using pre-planned anatomic boundaries.
Motion capture technology is then used to check the kinematics of the knee, which allows surgeons to fine-tune the bony cuts or make releases in the soft tissues to balance the knee.
What are the advantages?
Robotic knee replacement surgery has improved accuracy. The pre-operative plan can be executed to within 1 millimetre and 1 degree.
Robotic assisted knee replacements have more accurate implant positioning than conventional total knee replacements. There is currently no long-term data available for analysis to help draw conclusions about better functional outcomes or improved survival.
Early data for partial knee replacement from the AOA-NJRR shows that the revision rate was almost halved for robotic partial knee replacement at 3 years of follow-up. Partial knee replacements require training and experience to perform successfully. It is well established that surgeons performing partial knee replacements regularly have better outcomes than those with less experience. The tolerances for implant malposition are much lower in partial knee replacement, and this may be the reason for the improvement in revision rate when robotic assistance is used.
Short-term follow-up shows a lower revision rate for robotically assisted partial knee replacement.
Results from the Australian Orthopaedic Association National Joint Replacement Registry showing a survival advantage for robotically performed partial knee replacement.
Robotic knee replacements also have less post-operative pain and a faster time to discharge from the hospital. This is thought to be due to decreased trauma to the surrounding soft tissues in the knee, as the robot works to a pre-planned boundary.
Conclusion
There are many other factors that determine the success of a total knee replacement. These include appropriate patient selection, pre-operative planning, surgical approaches and techniques, post-operative pain management, and rehabilitation. Robotic assistance in knee replacement surgery is a useful adjunct for patients with complex knee pathology or for younger patients. The long-term results are yet to be determined, but the short-term results in partial knee replacement are promising.
Is knee pain affecting your quality of life? Don’t suffer any longer.
Read more about:
Osteoarthritis - What is it and how you can manage it.
Knee replacement - What the procedure involves and frequently asked questions.
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