I agree, no one would want to undergo another spinal surgery to convert an ADR to a fusion. There are cases on here where people were having problems a with certain disc i won't mention, and they tried leaving the disc in place and fusing around it. That NEVER goes over well. In the very rare case that should ever be necessary, find a quality surgeon who will get it out first. Dr. Clavel said he's needed to explant an M6 only 2 times that were not his patients, he claims he's done close to 2,000 M6's. One of the cases he was able to swap the M6 for another one. The other case he had to take it out and fuse because the disc space was too large to put another one back in...Neither case was due to failure of the disc, it was surgical error. Take that as you will.
All discs have a possibility for mechanical failure if enough forces are applied to the area, like say a real bad car accident. There are MRI's of discs(ball and sockets) that came completely off the nucleus. Can the nucleus shift under the right, extreme circumstances? Sure, just like any other disc out there. My point was if the annulus lost it's bond, i don't see that would interfere with the function of the nucleus, unless it's the woven annulus that's keeping the nucleus in place. Could be a good question to call SpinalKinetics about and ask them. If you have a fear about certain disc implants, by all means call them grill them about it. The more you know the better off you are. If you do, please post your findings here as many of us would love to know what new information you come up with.
