Quote:
Originally posted by lakezurich: I had a discussion with a spine surgeon regarding a new lumbar fusion implant and during the discussion also asked him about his opinion on artificial discs, Prosdisc as well.
He has a pretty strong opinion: It does not make sense at all and he would never use them. You gain 3º which compared to a fusion is very short of nothing and simply for this reason it does not make sense to use them.
To achieve this you may face considerable difficulties (migration and potential damage to the vertebraes among the most important) which could create real problems later on. He is of the oppinion that the hype these artificial discs create are pure marketing gimmicks.
He also gave me an advice which I feel is important:
When considering a spine operation always get an opinion of a surgeon with at least 100 operations per YEAR. Also try to get an opinion of an orthopedic suregon as well, and not only of a neurosurgeon because orthopedic surgeons have a better understanding of mechanics. |
Normal spine ranges of motion are:
Flexion - 10º
Extension - 5º
Lateral bending - +-5º
ProDisc ranges of motion are:
Flexion - 13º
Extension - 7º
Lateral bending - +- 10º
I don't know where the quoted information came from. My information comes from the ProDisc literature given to me under the FDA clinical trial. I doubt that SpineSolutions would be fudging numbers that are common knowledge to any orthopaedic surgeon, or numbers that can easily be measured.
I don't have the numbers for the Charite, but I've held a ProDisc and a Charite, side-by-side. I can assure you that the range of motion for these devices are similar. Both exceed the normal range of motion for your normal discs.
You may ask, "why would they implant a joint that is hyper-mobile... wouldn't that be a problem?" You must understand that they are not replacing the entire disc. After gaining access to the disc from the front, they cut a window that is just large enough to insert the prosthesis. Then, they remove the disc nucleus material, including the highly innervated tissue on the dorsal part of the annulus that is causing your discogenic pain. The endplates are then cleaned up, the prosthesis is inserted and the window in the annulus is sewn shut. All of the structures (annulus, ligaments, etc...) that limit the range of motion of your healthy spine are what limit the range of motion for the prosthesis. (This is why instability is a contra-indication for ADR. If your spine is unstable, it won't properly constrain the prosthesis.)
I don't know how much research the surgeon quoted above did, but the statement
"You gain 3º which compared to a fusion is very short of nothing and simply for this reason it does not make sense to use them." is simply false. It's unfortunate that so many patients are left with the responsibility for determining the difference between a well-researched, informed opinion and an uninformed opinion. We are used to believing what our doctors tell us.
Regarding migration and endplate damage. With over 5000 Charite's and 2000 ProDiscs worldwide, does the quoted surgeon have any information about rates for these complications? I don't know the numbers, but I'd be willing to bet that the migration rate for artificial discs is far less than it is for fusion hardware. How about endplate damage for a failed ALIF with cages... especially cages that are drilled and screwed through the endplates. So, is the reservation about these potential complications well researched and informed? I wonder what specific information he has that would allow him to say that all the fuss about artificial discs are from "pure marketing gimmicks?"
I hope this is clear. My ordeal ended with my successful 2-level artificial disc surgery in Munich in September, 2002. I now play tennis, ski, SCUBA dive, rock-climb, etc... That's after 3 spine surgeries, endless meds and no life for 3 years. I was sightseeing around Munich less than 2 weeks after my surgery. After 3 straight years on opiates, Neurontin, and anti-depressants, I started tapering off the meds at 2 weeks post=op. At 6 weeks post-op I took my last narcotic. That was over 4 months ago and I haven't had one since. That is some marketing gimmick, isn't it!
Challenge everything... discuss it until you understand it. Continue to explore it and 6 months later, you'll discover that what you thought you'd understood was all wrong. This is a difficult process... keep working at it.
Good luck!
Mark