study of failure

[johnb]

http://www3.aaos.org/education/anmee...cfm?Pevent=111

This was posted in the article library and was grouped in with several others studies. I've seen questions appear in threads that are addressed here. It is a subset of several I.D.E. studies of 3 different manufacturers disc with more strict criteria for success than what the FDA mandates. Of the failures, 46% were facet related. These being I.D.E. studies, pre existing facet problems would have excluded someone from the study. I also found it interesting that the study concluded that some manufacturers disc perform better than others.

There are other studies that were grouped with this one that probably answer other question on the board. For example, there is another study that shows MRI is inferior to CT in diagnosing cervical facet problems. My experience supports this even though my problems are lumbar and not cervical. I was told that my facets were enlarged but okay looking on my MRI for ADR but insurance blocked my surgery. I underwent dynesys instead and my facets fused in the first 3 months as they were bone touching bone. The surgeon didn't tell me I was gonna end up with a posterior fusion.

I'd suggest anyone with questions peruse the AAOS group of articles that were posted in the article library. Thanks slackwater for your keen ability to post relevant info. You are research machine!!! Here is the post containing the presentations. http://www.adrsupport.org/forums/showthread.php?t=9768

Here is the article on cervical facet arthrosis. I'd like to see the same study done with lumbar. http://www.adrsupport.org/forums/showthread.php?t=9692

John

[Harrison]

Thanks John, for calling attention to these important issues and articles. And thanks to Slack for posting the study references!

[Slackwater]

Originally Posted by Harrison

Thanks John, for calling attention to these important issues and articles. And thanks to Slack for posting the study references!

Thanks to both of you for looking at the data. Maybe English is not my first language ?
I found the abstract short (by definition) and I look forward to reading an article in
The Spine Journal, Spine, JBJS, or ... to make sure I understand the numbers.

I want to know about "placement" or "positioning" of the implants in relation to "clinical failure" in regards to facets.

One surgeon at 2009 AAOS related the non-MCID (failure?) ADR patients
to those who might have rec'ed fusion with the same result, non-MCID.
MCID - Minimal Clinically Important Difference


To my limited understanding:


Kineflex-L was randomized against Charite'. Link
Kineflex: Experimental Device: Artificial Disc Insertion of Kineflex Disc
Charite: Active Comparator Device


Maverick was randomized against Fusion w/Infuse Link
MAVERICK™ Disc: Experimental Device
Fusion Device: LT-CAGE® Lumbar Tapered Fusion Device and INFUSE® Bone Graft (Fusion)


The numbers I want to see are Maverick v. Fusion
with 50% decrease in VAS & ODI as success criteria


Quoting from the AAOS Abstract:


Failure was defined as less than 50% improvement in O.D.I. and V.A.S. or any additional surgery at index or adjacent spine motion segment. This criterion for success was more stringent than F.D.A. guidelines, which require only a 25% improvement in O.D.I. and V.A.S. for clinical success.


The type of A.D.R. makes a difference.
(ed: ?? uhh, maybe? but this assumption is based on a small number of patients, a subset of the total trial )

Causes of failure included: facet pathology 46% of failure patients,( 11 of 24).
(ed: ??? uhh, what was the Anterior/Posterior and Coronal ED:side-to-side positioning ?? )
( essentially every biomechanical study shows A/P and side-to-side affects facets etc. )


Implant complications occurred in 6% of the total patients and 25% of the failure patients, (6 of 24).
(ed: ~understand the relationship)

Patients with additional orthopedic or medical pathology or disability/narcotic issues making them unable or unwilling to fill out follow-up forms specific to their A.D.R. occurred in 29% (7 of 24), of the failure group.
(ed: agree, there are other factors, makes me want to know how many had other
non-related issues in med.pathology, disability( psychological, lawsuit ? probably not,
never would have been allowed in the trial), narcotic & did not fill out the forms ?? )

Despite the fact these patients were considered failures based on O.D.I. and V.A.S., they reported a 92% satisfaction with the A.D.R. and would repeat the surgery for the same result.


Interestingly, A.D.R. patients are often either a clinical success at three-month follow-up (home run) or a possible failure (strike out). Only five patients went from a success to failure after three months. One was an infection one year after A.D.R. and four patients developed additional pathology unrelated to their A.D.R. Only one patient went from a failure to success after a facet rhizotomy one year after A.D.R.

[Slackwater]

Originally Posted by johnb

http://www3.aaos.org/education/anmee...cfm?Pevent=111

For example, there is another study that shows MRI is inferior to CT in diagnosing cervical facet problems. My experience supports this even though my problems are lumbar and not cervical. I was told that my facets were enlarged but okay looking on my MRI for ADR but insurance blocked my surgery. I underwent dynesys instead and my facets fused in the first 3 months as they were bone touching bone. The surgeon didn't tell me I was gonna end up with a posterior fusion. (Wow, Surprised to Read This)

I'd suggest anyone with questions peruse the AAOS group of articles that were posted in the article library. Thanks slackwater for your keen ability to post relevant info. You are research machine!!! Here is the post containing the presentations. http://www.adrsupport.org/forums/showthread.php?t=9768

Here is the article on cervical facet arthrosis. I'd like to see the same study done with lumbar. http://www.adrsupport.org/forums/showthread.php?t=9692

John

I wish there was a magic wand, reading the above reinforces the thought.

MRI is in some respects inferior to CT, micro-CT and other imaging techniques, but ... a lot of diagnostics need to be upgraded.

[johnb]

The same thing happened with cervie queen. She posted that here on the forum sometime ago.

http://www.adrsupport.org/forums/showthread.php?t=7754

John