Technology has transformed many areas of modern medicine, and orthopaedic surgery is no exception. Knee replacement surgery, in particular, has increasingly incorporated computer-based planning, digital imaging and robotic-assisted systems.
For patients considering a knee replacement, however, the technology can sometimes be difficult to understand. Terms such as “robotic knee replacement”, “computer-assisted surgery” and “robot-assisted surgery” are increasingly used, but they do not necessarily mean that a robot is performing the operation independently.
Instead, these technologies are designed to support the surgeon during particular parts of the procedure.
How is technology used in knee replacement surgery?
A knee replacement involves removing damaged areas of the joint and positioning artificial components so that the knee can function as comfortably and effectively as possible.
Traditionally, surgeons have used instruments, measurements and imaging to plan and perform the procedure. Modern technology can add another layer of information.
Depending on the system being used, technology may help with:
- planning the position and alignment of the implant
- creating a digital model of the patient’s knee
- assessing the balance and movement of the joint
- providing real-time information during surgery
- helping the surgeon follow a planned bone-cutting or implant-positioning strategy
- recording information about the procedure
The precise technology varies between systems. Some use pre-operative imaging, while others create information about the joint during the operation.
NICE currently recognises six technologies for robot-assisted knee or hip replacement in the NHS during an evidence-generation period: ApolloKnee, CORI, Mako SmartRobotics, ROSA Knee, SkyWalker and VELYS.
What is robotic-assisted knee replacement?
Robotic-assisted knee replacement is not a completely different type of knee replacement. It is better understood as a technology used to assist the surgeon in planning and carrying out the operation.
The surgeon remains responsible for the operation.
A robotic system can provide information about the patient’s anatomy and help the surgical team plan implant positioning. During the operation, some systems use a robotic arm or other technology to help the surgeon follow the planned approach.
The exact way this works depends on the particular system.
Some platforms use imaging to create a three-dimensional representation of the joint. Others use information collected during surgery without requiring the same type of pre-operative imaging.
This distinction matters because “robotic knee replacement” is sometimes presented as though there is one standard procedure. In reality, there are several different systems and approaches.
Does a robot perform the operation?
No.
The term “robotic-assisted” can give the impression that a machine independently carries out the surgery. That is not what happens.
The surgeon performs the operation and uses the technology as an additional tool.
NICE describes robot-assisted surgery as surgery in which robotic technologies support the work of the surgeon, providing information such as real-time imaging and feedback.
This means that the surgeon’s experience, clinical judgement and understanding of the patient’s individual circumstances remain important.
Technology does not remove the need for surgical decision-making.
Why might a surgeon use robotic assistance?
One potential advantage of robotic-assisted surgery is that it can provide detailed information about implant positioning and alignment.
NICE found that implant alignment was consistently more precise with robot-assisted surgery than with conventional techniques in the evidence it reviewed. However, the committee also noted uncertainty about whether greater alignment precision necessarily results in better clinical outcomes for patients.
This is an important distinction.
A technology can make a particular aspect of an operation more precise without necessarily proving that patients will experience substantially better long-term results.
For patients, therefore, it is sensible to ask not simply whether a hospital offers robotic surgery, but why the surgeon believes it is appropriate for their particular knee.
Is robotic knee replacement better than conventional surgery?
There is no simple yes-or-no answer.
Research has compared robot-assisted and conventional knee replacement, but the evidence is still developing. NICE’s current assessment found broadly similar outcomes for important measures such as complications, patient-reported outcomes and revision surgery, while implant alignment was more precise with robotic assistance. The committee was uncertain about whether this difference in alignment produces better clinical outcomes.
This means patients should be cautious about claims that robotic surgery is automatically “better”.
The technology may offer advantages in particular circumstances, but it does not mean that conventional knee replacement is an inferior treatment.
NICE has therefore recommended that evidence continues to be generated while these technologies are used in the NHS under its early value assessment framework.
What other technology is used in knee replacement?
Robotic systems are only one part of the technology used in modern joint replacement.
Digital imaging can help surgeons understand the patient’s anatomy before surgery. Computer-based planning can assist with determining the proposed position of implants, while intra-operative technology can provide information during the procedure.
Different hospitals and surgeons may use different systems.
Some technologies are designed for total knee replacement, while others can also be used for partial knee replacement or other procedures. The compatibility between a particular robotic system and implant can also vary. NICE notes that the technologies assessed differ in their functionality, imaging requirements and implant compatibility.
Does having robotic surgery mean recovery will be faster?
Not necessarily.
It is tempting to assume that greater technological precision must automatically lead to faster recovery. However, recovery from knee replacement depends on many factors.
These include the patient’s health and fitness, the condition of the knee before surgery, the operation itself, pain management, rehabilitation and the individual’s response to treatment.
NICE has identified evidence gaps around outcomes such as quality of life and resource use, including whether robot-assisted surgery affects hospital stay, rehabilitation requirements or other healthcare use.
Consequently, patients should be wary of guarantees about faster recovery based solely on the use of robotic technology.
What should patients ask about robotic knee replacement?
If robotic-assisted surgery is being offered, a consultation is an opportunity to understand exactly what is being proposed.
Useful questions include:
- Which robotic system is being used?
- Why is robotic assistance appropriate for my knee?
- Would conventional knee replacement also be suitable?
- What type of knee replacement am I having?
- How frequently does the surgeon perform this procedure?
- What evidence supports the use of this technology?
- Which implant will be used?
- Does the robotic system require additional imaging?
- Are there additional costs associated with the technology?
- What are the expected benefits in my particular situation?
- What are the risks?
- What rehabilitation will I need afterwards?
These questions can help separate the technology itself from the overall quality of the treatment.
Technology is a tool — not the whole treatment
Robotic-assisted surgery represents an important development in modern knee replacement, but it should be viewed in context.
The technology can provide surgeons with additional information and tools for planning and performing an operation. It may improve the precision of certain aspects of implant positioning, but current evidence does not establish that robotic assistance automatically produces better outcomes for every patient.
For someone considering knee replacement, the most important question is therefore not simply “Does this hospital have a robot?”
It is:
“Is this the right operation for me, and how will this technology contribute to my treatment?”
Understanding the proposed procedure, the surgeon’s experience, the evidence behind the technology and the expected recovery can help patients have a more informed discussion before making a decision.
For patients who want to understand the technology in more detail, robotic-assisted knee replacement is one area worth discussing with an orthopaedic surgeon before deciding whether it is appropriate for their individual circumstances. For more information regarding private knee replacement surgery visit Active Again for their recent patient information guides.
