If you need a knee replacement in middle age, what’s the problem? Jon Smith explains.
A couple of months back, my YKC colleague Dave Duffy wrote about age and knee replacement. He asked how old is too old for a knee replacement – you can read his post here.
But that begs an obvious question. At the other end of the spectrum, is it possible to say how young is too young for a knee replacement?
How young is too young for a total knee replacement?
For a total knee replacement or TKR (that is, a resurfacing of all the compartments of the knee), there’s lots of evidence that the older you are the happier you’ll be with your new knee. This study on the optimal age for a total knee replacement settled on “around 70”. That was based on PROMS, ‘patient-reported outcome measurements’ in which patients are asked about their pain and function levels and their overall happiness with the implant.
The news isn’t so good for younger patients, and for one simple reason: the younger you are, the more you’re likely to ask of your knee implant. At 55, you’ll almost certainly still be working. You may be extremely active. You may regularly be taking part in sport. In your 70s, whilst you could still be doing all of those things, the likelihood of placing quite the same demand on your knee is less.
This issue of functional demand is an important one. Knee implants have progressed impressively over the past couple of decades and are now likely to last many years. But no implant is indestructible and the more you do, the faster your implant is likely to wear out. When that happens, you can’t have a second TKR. It is possible to revise a TKR (that is, give it a major overhaul), but the results will never be as good as the original implant, and with each successive revision, function will be a little worse and pain will be a little more.
So the younger you are when you have a TKR, the more likely you are to run into issues later down the line and the less likely you are to be completely happy with it post-op. I usually advise that around 1 in 4 younger patients are likely to feel some dissatisfaction, but those expressions of dissatisfaction reduce significantly with age. For all these reasons, I would be extremely wary of carrying out a TKR on anyone aged 55 or younger.
How young is too young for a partial knee replacement?
It’s a different story with partial knee replacement (PKR). In a PKR, just one compartment of the knee is resurfaced. It’s a far less radical procedure, recovery times are faster and, crucially, when it eventually wears out years down the line, you retain the option of having a TKR. PROMS are extremely positive across all demographics, especially when your PKR is carried out by a specialist.
We know that 70-75% of patients who require a knee replacement are suitable for PKRs, and I wouldn’t generally have any concerns about performing a PKR on a 50-something.
What happens if I need a TKR?
You’re 55. Your knee pain is agonising. You’re not suitable for a partial knee replacement. The dilemma, therefore, is do we carry out a total replacement in the full expectation that it won’t be a perfect solution, or do we refuse and leave you in pain until you reach 70?
The answer, of course, is that we operate, but it is vital that patients understand that a TKR is not necessarily a golden ticket to a knee that feels as good as it used to.
That is far more likely to be the case with a PKR, and it’s why all Yorkshire Knee Clinic’s surgeons advocate the use of partial knees for all suitable patients.
Can I Have A Knee Replacement?
What’s the difference between a total & partial knee replacement? And is either right for you?
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