Stabilization (PDS) behind ADR?

[Liz]

Does anyone have experience with, or any knowledge of, posterior dynamic stabilization (PDS) behind ADR?

I'm not comfortable with the mixed results of Dynesys. I've been waiting for FDA approval of some flexible rods made by Globus that are designed to work with scoliosis but they are upheld by the FDA. I also heard good things about Applied Spine's Stabilimax PDS but it got pulled from the market and the US clinical trial is suspended. so it's a great time to need a stabilization! I'm curious if the PDS failures are a result of altering the biomechanics of the spine, too much motion, etc.

If you have any info/experience with any type of PDS with ADR please send me a PM if you're not comfortable posting on the forum.

thank you!

Liz

[berry]

Hi Liz

There's some info on a dynamic stabilization system from Paradigm Spine in the link below. It doesn't say that is for use after ADR specifically though but perhaps the manufacturers could be contacted to answer any questions. (Its not available in the US yet either but may still be of interest.) If I find anything on PDS following ADR I'll let you know.

http://paradigm-spine.de/web/DSS_Pro...p?hmenu=Lumbar

Kind regards

Lynda

[Liz]

Bumping this up hoping for more responses!

Lynda, thanks for the info! surprisingly, i haven't heard from anyone other than our friend Cathy (down under), whom we know is struggling w/Dynesys behind her L4-5 Maverick.

Since i think this is an important topic (especially as more people are facing ADR revisions), i'll add what i've learned for anyone that's interested...

I contacted Paradigm Spine, but they just told me that DSS is approved for a strict set of indications in the US and that treatment is up to my surgeon. They kindly directed me to two surgeons in the western US that were trained to use the DSS.

I contacted Drs Bertagnoli and Fenk-Mayer as Dr. Bertagnoli helped develop the DSS (a pedicle screw stabilization). Dr. Bertagnoli has used DSS behind ADR, but it sounds like only in a few cases. He has also used Paradigm Spine's Coflex (interspinous stabilization) behind ADR for cases of stenosis. He is no longer using Dynesys because of the new, improved devices.
This article somewhat explains the difference in Dynesys and DSS, http://www.neurocirugia.com/instrume...y080215-190446

Dr. Bertagnoli is also using a new Total Spine Motion Segment by Disc Motion, which includes a posterior ADR and a PDS that unloads the facets, http://www.discmotion.com/product_intern.htm
In theory, this sounds like a great concept to me for the right patients/indications but I don't know much about it.

Dr. Zeegers also uses Coflex behind ADRs, and I'd guess many surgeons outside the US do as well.

currently, Coflex is in clinical trial in the US, http://clinicaltrials.gov/ct2/show/N...=coflex&rank=1

The PDS i have been waiting for made by Globus (Transition PDS) is still not FDA approved... FDA approval is expected w/in the next 3-6 months. It is upheld b/c as previously mentioned some stabilizations by other manufacturers have failed in non-ADR patients so others are being more closely scrutinized. Of course this makes me skeptical of stabilization in general, but my options are limited so I'm just trying to find the best one for my spine.

i have spoken with two patients unaffiliated with this forum whom have two-level L4-S1 stabilizations behind ADRs (Dynesys w/Prodisc and Coflex w/Active-L) and both are doing fairly well. While surgeons claim stabilizations are minimally invasive, both of these patients told me the recovery was very long and painful.

I will keep this updated as I learn more.

anyone with info/experience with a stabilization please contact me or post here!

thanks!

Liz

[berry]

Hi Liz

Thanks very much for bumping this up, it is interesting to learn what you have discovered. We have discussed the Total Spinal Motion Segment device briefly on the UK site. The Disc Motions Technologies website is very interesting I find, the company, it appears, was founded by a Mr Krishna, a Consultant who set up the North Tees University Hospital Spinal Unit in the UK.

It seems he and colleagues designed and patented a posterior lumbar disc replacement system which is the first TOTAL joint replacement for the lumbar spine, the True TSMS (Total Spinal Motion Segment) System……how very interesting indeed. As someone who has gone on to develop facet arthrosis after my lumbar TDR’s I find this intriguing.

Quote from the Disc Motion Technologies website:

“The True TSMS™ (Total Spinal Motion Segment) System

Disc Motion Technologies has designed and patented the first posterior lumbar spinal arthroplasty system designed both to preserve motion and address all of the pain generators in the motion segment; the disc, the facets and the neural components. The True TSMS™ system features the first posterior disc, a posterior dynamic stabilizer with center of rotation that corresponds to that of the disc and mono axial screws.”


From what I understand (one of the UK members has spoken to his secretary) two patients have had the system in the UK and 'others' abroad but I have no knowledge of their outcomes; perhaps this is the way forward in the future??? It will be interesting to watch developments and see the results of long-term studies.

The disc motion website has a link to a case study of a female patient in Turkey who received this system in July 2008. http://www.discmotion.com/news.htm

Coflex is in use in the UK (Mr Shackleford uses it) and one of the UK forum members has had it for spinal stenosis with good results.

If I find any more information I'll be in touch.

Kind regards and best wishes to you Liz

Lynda
xx

[Justin]

Liz, did you hear from Drs. Bertagnoli and Fenk-Mayer? I'm still waiting--that man is like a machine, it's unreal! I'd be happy working half as hard as he does.

[Liz]

Originally Posted by Justin

Liz, did you hear from Drs. Bertagnoli and Fenk-Mayer? I'm still waiting--that man is like a machine, it's unreal! I'd be happy working half as hard as he does.

Justin... sorry, i guess i cut the queue! i don't know what to tell you... i guess it's ladies first at Pro-Spine .
i emailed Drs B and F-M at midnight Sunday and they responded Weds AM -- very impressive. Some of that response is in my post above. i hope Dr. B calls you soon... i'm sure the suspense is driving you crazy.

Lynda... thanks for the additional info! I appreciate it.

happy holidays to both of you!
Liz

[Justin]

Originally Posted by Liz

Justin... sorry, i guess i cut the queue! i don't know what to tell you... i guess it's ladies first at Pro-Spine .
i emailed Drs B and F-M at midnight Sunday and they responded Weds AM -- very impressive. Some of that response is in my post above. i hope Dr. B calls you soon... i'm sure the suspense is driving you crazy.

Lynda... thanks for the additional info! I appreciate it.

happy holidays to both of you!
Liz

I've been left behind! Thanks for cutting the line BTW. The suspense is driving me insane. I think I'll cry now.

[Terry]

Originally Posted by Justin

I've been left behind! Thanks for cutting the line BTW. The suspense is driving me insane. I think I'll cry now.

I hope you get some answers soon Justin. I drove the 520 miles today for the annual trip to Elizabeth's family for Christmas. I was somewhat sore due to the drive but, no where near as bad as I would have been without the injections. I am hanging in there.

You do the same buddy. Women can cut in line due to being the fairer sex. We will get in to heaven faster.

Terry Newton

[Justin]

Originally Posted by Terry

I hope you get some answers soon Justin. I drove the 520 miles today for the annual trip to Elizabeth's family for Christmas. I was somewhat sore due to the drive but, no where near as bad as I would have been without the injections. I am hanging in there.

You do the same buddy. Women can cut in line due to being the fairer sex. We will get in to heaven faster.

Terry Newton

Terry,

Wow that is quite a drive. It sounds like you did really well! Have a most wonderful Christmas with the family. I will hang in there my friend.

Very true about women being the fairer sex. Just because sarcasm is hard to read on the forum: everyone I was giving Liz a hard time (you know this Terry). Just don't cut in line again Liz. [/sarcasm]

[Liz]

Lynda,

I thought you might find this interesting...

from: Motion Preservation of the Spine (May 2008),
http://books.google.com/books?id=AJ5...sult#PPA735,M1

Go to page 735 -- Chapter 94 -- Posterior Lumbar Arthoplasty by Mr. Krishna. This chapter discusses the TSMS in detail... I found the discussion on matching the instantaneous axis of rotation (IAR) of the ADR and PDS very interesting (among other things)... perhaps this is partly why some ADR/PDS combinations fail. Such a crapshoot. Other PDS devices are also discussed in the book. Lots of info in this book... some pages (along w/all images due to copyright) are missing from the preview, but you'll get the idea and you can buy the book from Amazon for almost $300... yikes.

I've been told it is possible to revise a Prodisc to the TSMS, but of course this would be a very invasive surgery. Any volunteers to try this out?

I think most people that have to remove a Prodisc (or any keeled ADR) will opt to fuse the segment rather than putting in another ADR (or even an experimental PDS) but I'm just in an unique and complicated situation where I really don't want to fuse my compensatory curve (and I have DDD at adjacent segments). Getting off topic, but keeled ADRs (including Prodisc and Maverick) that are removed laterally are fused b/c bone has to be chipped away to remove the keel; if the keeled-ADR can be removed the way it went in (anterior) then a revision to another ADR is possible. This is where the effectiveness of vessel guards will hopefully come into play.

Liz