This week sees a gathering of the mostly European “great and good” of meniscal surgery, with the holding of the 2nd international meniscus meeting in Versailles, France between Feb 7th and Feb 9th. Just how far things have moved on in meniscus surgery over the past twenty years is debatable. No doubt meetings like this, with such specific focus on one tissue type, exist to drive things on a bit.
The dynamics of what’s happened in meniscal surgery since the early eighties are fascinating and provide a nice contrast with what’s happened with, for example coronary artery disease. In both cases things have moved on, but the extent to which progress has occurred in the two fields could not be more stark.
Firstly the meniscus. Back in about 1983 I recall seeing a picture of a famous British footballer brandishing what looked like a piece of uncooked calamari for the camera. It was of course the lateral meniscus, in its entirety, from one of his knees. “Having one’s cartilage out” was a common surgical procedure in those days, the troublesome lumps of innocuous-looking material being considered “better out than in”, especially for people engaged in active sports at a high level.
Arthroscopy meant we could see the damage
Not long afterwards, arthroscopy as a discipline became mainstream and the view it afforded of the inside of the knee suddenly made the meniscus look rather bigger and altogether more significant, sowing seeds of doubt that its complete removal was always such a good thing. It clearly had a well-understood function and there was an understanding that the joint was no longer as well protected without it as it was with it.
To say any orthopaedic professional really thought that was the case is doing them a disservice. The fact of the matter was that the tools didn’t exist to do much other than chop it out. Then, in one of the stepchanges in the specialty, the so-called hand-held arthroscopic instrument appeared. These tools probably changed things as much as the arthroscope itself. Now surgeons could get to all parts of the knee and accurately excise the torn tissue, leaving behind at least some of the knee’s protection/stabilisation/mobility-giving mechanism.
Meniscal repair… a minority procedure that everyone was talking about
Then in the late 80’s folk started actually repairing torn meniscus, at least the bits thought to be repairable, namely the red/red periphery. The earlier devices with their parallel cannulations, down which sutures could be passed, worked well, but were superceded by clever all-inside gizmos, most notably the Meniscus Arrow. The “Arrow” was in fact a barbed tack, tapped or later “fired” into the meniscus, across the tear, ultimately to resorb, to leave a nicely healed complete meniscus. The Arrow hit the buffers somewhat when reports appeared of incorrectly or inadequately seated implants standing proud of the meniscal surface and creating wear damage to the femoral condyles.
The next iteration of repair devices are still variously in use today, having replaced the condyle-side protrusion with knots or locking mechanisms that sit behind the meniscus.
Meniscal implants… nowhere near mainstream yet
All of this left the problem of the unrepairable meniscus, remembering that fixing tears in the inner two thirds without a blood supply, is about as easy and effective as sticking the white bit of your finger nail back on. It doesn’t work, especially in the highly stressed environment that is the inside of the human knee.
The obvious answer, as long ago as the very early nineties, was some form of implant. Several were tried, and the fact that not one is FDA approved today rather tells the tale that either they didn’t work very well or that the agency is adopting a wait and see approach as clinical data is collected.
One such device is the Actifit® implant from Orteq®, that’s been on the Eu market since 2008. This device comprises a polymeric scaffold that ultimately resorbs, and has been given a clean bill of health from the UK’s NICE watchdog. While that “approval” doesn’t mean NICE has established that the device works, it does mean that they have no significant safety concerns. Having said that, the advice provided on the NICE site is not exactly a ringing endorsement for the technology, stating that it should only be used under special clinical governance conditions and that there are uncertainties about any possible long-term advantage over other surgical options and that considerable rehabilitation is required after the procedure.
Settling on a meniscal treatment regime remains elusive but desirable
So where next for the meniscus? Well, meetings like the one being held this week are clearly important. Addressing meniscal lesions is one of those subjects that looks a bit piffling at first glance. But imagine the impact on patients and healthcare costs if we could prevent or delay more radical joint surgery by simply replacing a torn meniscus, remembering that a torn or missing meniscus is virtually guaranteed to lead to damage of the articular cartilage itself.
Meanwhile, in the cath lab
The premise for this piece was the contrast with interventional cardiology. Around the same time people were chopping entire menisci out, people with coronary heart disease were being faced with the old Cabbage (CABG) procedure… Coronary Artery Bypass Graft. Some are still done, but nowadays the idea of sawing open the sternum and grafting in a piece of an artery from somewhere else on the body (usually the leg), has been rendered somewhat obsolete by technology. What started as a clever navigation exercise from the groin to the target lesion in the coronary artery quickly advanced to therapeutic solutions for blockages in the form of tiny balloons which compressed dangerous plaques onto the vessel walls. Then those balloons became delivery devices for dispensing of metallic stents to prop open the vessels. But the thrombogenic nature of those implants meant a lifetime of suppressive drugs and blood thinners, so next came the drug eluting stents and now the absorbable stents.
That’s just one example. We could talk about transcatheter heart valve implantation or endoscopic aortic aneurysm graft insertion, but the point is made.
So have advances in meniscus surgery been too slow? Indeed has the motivation to for companies to invest in and deliver new therapies been too low? Or is it just that the inside of the knee is such a harsh environment that the challenge is too significant? Who knows, but what I do know is that if you attend a knee arthroscopy today it looks like it did in 1993. If you’ve had a heart attack, your treatment is likely to be very different.