Just a gentle warning: the Verilast is certainly as good as any other knee so please don't think I'm saying otherwise, but the wording on that website is a great example of marketing hype!
For instance
1. a combination of remarkable materials that were tested to simulate 30 years of wear performance. That’s more than twice the length of testing of knee replacements made from traditional materials.
2. (and) that is more resistant to common implant wear. When these two surfaces work together in the joint, they do amazing and unprecedented things
3. was subjected to 45 million cycles, or simulated steps. That’s equal to around 30 years of physical activity.
Now these statements may well be true but it reads like this a new development which is exclusively applicable to this knee which isn't. It's actually a pretty average performance for all knees! TKRs have been lasting for 30+ years for decades!
And there is a nice little caveat in the paragraphs at the bottom which, having read all the 'good' stuff, people may not bother to read or absorb.
The results of in-vitro wear simulation testing have not been proven to quantitatively predict clinical wear performance. Also, a reduction in total polyethylene wear volume or wear rate alone may not result in an improved clinical outcome as wear particle size and morphology are also critical factors in the evaluation of the potential for wear mediated osteolysis and associated aseptic implant loosening. Particle size and morphology were not evaluated as part of the testing. Other risks can include loosening, fracture, dislocation and infection.
Do not perform high impact activities such as running and jumping unless your surgeon tells you the bone has healed and these activities are acceptable.
This too is applicable to all joint replacements. And note the change in literary style from consumer friendly to scientific!
All I am saying is, do be careful to take a pinch of salt with what you read. Carefully written, the text can easily make the standard sound like a new miracle development! It is, after all, a sales pitch.