Welcome, chiro Kappa! Sorry about your health situation. BTW, were you deployed to the Gulf? I was just wondering relative to any mycoplasmic infections (see Dr. Garth Nicolson’s work). What MRIs or X-Rays have you had? Any pending?
Here’s my opinion on your questions, using Anna’s approach:
Q: If the motion from the ADR is not the same as physiological motion, you are putting your posterior motion segments(ie facet joints) at risk for premature degeneration.
A: This continues to be a heated debate among informed patients, and (I believe) less so in the scientific circles. Docs/mfrs have the lead advantage of reviewing and analyzing the long-term outcome data before it is disseminated via the Internet. More on this soon in another new topic.
Q: Also, at the L5-S1 level there is very little motion to begin with, so are you really affecting the spine biomechanics considerably by laying the motion segment to rest?
A: The 5 and 10 year Charite outcome data reveals incredibly low adjacent level lumbar disc degeneration (app. 2-3% I believe), far lower than fused lumbar segments. Little motion at L5-S1? I doubt this is true for most people – especially active, young folks – just my layman’s opinion.
Q: I've heard about problems with discs fitting the vertebral body end plates properly.
A: For this reason, sizing of the end plates is critical. This is the surgeon’s job and they are carefully trained for this. (Some patients suffered through subsidence issues; much has been learned, thanks to the "patient pioneers.") This concern is also an argument for other disc designs, such as the Active L, which purports to “cradle” or cup the entire vertebral body, distributing weight & force evenly. For people susceptible to osteoporosis, they should think carefully about this issue and talk to their surgeon about their concerns.
Q: Also, problems with pitting and wear in the polyurethane core.
A: AnnaPurna raises a good point, and their (2 folks behind the screen) scientific prowess is no match for me! But there are many documents and past topics on this. Here’s one:
Publication: Wear Particles and ADR
http://adrsupport.org/eve/forums/a/t...8961041281/p/1