Are totally personalised knee implants the solution to dis-satisfaction with knee-replacement surgery?

Total knee replacement is an effective and successful treatment for osteoarthritis of the knee. Prior to the pandemic around 100,000 knee replacement surgeries were taking place in the UK each year. Nevertheless, dis-satisfaction with the outcome following surgery is surprisingly common, with studies repeatedly showing that as many as 20 per cent of people who undergo knee replacement are unhappy with the results and a significant number of patients remain dissatisfied following this procedure. Underpinning this is disappointment in the actual improvement in knee function and continuing pain.

Compromises in knee fit, rotation and alignment

A number of leading knee surgeons believe that the problems experienced with knee replacement are linked to the use of "off the shelf" implants, which come in a range of fixed sizes that have to be made to "fit" by making necessary adjustments during the surgical procedure. Further, there is just one shape, designed to match the "average" knee. However, every single knee has a unique shape and set of curves and the way that each individual knee bends and extends is of course determined by the natural shape of that knee. Replacing one shaped knee with an implant that is a different shape will mean that it is unlikely that the knee will now be able to move in the same way (joint kinematics) and is less likely to feel "normal." The sizing and shape limitations of standard implants, then, can lead to compromises in fit, rotation and alignment, which in turn result in instability and pain - one of the primary reasons for having surgery in the first place.

Size and shape matter in joint replacementCustom joint lines are maintained

What many people considering knee replacement surgery are not aware of is that it is possible to have a totally customised knee implant that will exactly match the unique size, shape and contour of their own knee. The Conformis knee replacement system utilises CT scan images and 3-D printing technology to create individual, personalised implants that exactly match the size and shape of each patient's unique anatomy. By following the shape and contour of the existing knee the joint lines are maintained and the knee can move more naturally resulting in less discomfort and pain.

Obtaining optimal outcomes

Knee specialist Mr Ian McDermott was the first surgeon in the UK to use the customised system back in 2012. A decade later he has performed several hundred surgeries using the tailor-made implants and he has no doubt about the benefits for his patients. He states: " I want the absolute best for each and every one of my patients and the way that I feel I can achieve this is by recommending a personalised implant."

Research confirms this view with the Conformis iTotal knee replacement system demonstrating superior clinical outcomes, including better function and greater patient satisfaction (90 - 95 %), compared to traditional, "off-the-shelf" implants.

When it comes to satisfaction with knee replacement, size (and shape) really do matter.

See video - Is a bespoke knee implant the gold standard in total knee replacement?

Inflammation of one or more joints of the body. Full medical glossary
The abbreviation for computed tomography, a scan that generates a series of cross-sectional x-ray images Full medical glossary
A disease mainly of the large joints of the body, as a result of wear and tear of the surface cartilage. Full medical glossary
An outbreak of infection that affects numerous people in different countries. Full medical glossary