Gelstix - Personal Addendum


Personal Addendum

I have done slightly more than 50 cases between Nov 2011 to March 2012. 35 lumbar and 15 cervical cases. Briefly, the results show reduction in VAS from between (7-8) to between (2-3). I did these cases as a part of a large cohort of 600 patients between 2004 to early 2012 to evaluate the difference in outcome of the intradiscal treatments. my work can be accessed from the ISMISS/PESS meetings of Dr Leu in zurich, where i have had presentations in 2012, 2010 and 2009; in lumbar intradiscal treatment outcomes. To be honest; my current results show that the gelstix is as good as any other intradiscal procedure; and i could not show any significant difference when comparing with my other patients who had IDET, Dekompressor, Nucleoplasty or Disc-fx in the 3 month follow up results. i believe that the gelstix will prove to be superior in the long run (perhaps in the 2-5 year follow up); but it remains to be seen. consider using the gelstix as a (nucleus augmentation) device together with either a nucleoplasty, or a Stryker deKompressor. while you will note that the traditionally trained spine surgeons will run down these treatments; i have found it to be most acceptable to my patient patient population. i agree that that the ideal indication is the patient between conservative treatment and fusion; however, i have not had any from my gelstix cohort who has asked for a fusion in this one year.

To date in the 50+ cases; i have not seen or had any complications. there were 2 lumbar patients who did not have the expected pain relief; but for reasons not related to the implant of technique of implantation.
Harwant Singh, MD, FRCS, PhD.


Letter to Dr. Tanner,

1) I initiated the trial with Dr. R. Morgenstern in Barcelona and performed several cases with him starting in 2010

2) The first 11 cases generally adhered to the Company clinical indications defined in the IFU but there were several exceptions. There have been over 400 cases done worldwide (Spain, Italy, Malayasia, Asia, Mexico)

3) The patients had more collapsed discs than was advised and some of the patients had moderate to severe DDD based upon modic changes and Pfirrman classification. A couple of cases were treated with a spondylolisthesis and these patients didn't do as well.

4) The intention of the study was to treat a broader base of patients and then refine the patients to treat the remaining cases with a more defined indication. There is data out to 1 year on the first 6 cases and a number of patients treated for less than 1 year.

5) Of the 15 controlled pts (Spain), 1 pt had continuing pain and were revised to a fusion. No implant failures or migrations were noted.

James J. Yue, M.D.
Associate Professor
Department of Orthopaedic Surgery
Spine Surgery
Yale University School of Medicine


Letter to Mr Knight

However, with respect to the GelStix applications, it is very important to recognize that the GelStix has been specifically designed to be introduced through a very small puncture through the annulus.

The data we have been accruing clearly supports retention in the disc space when the device is implanted under carefully controlled conditions including, implantation using a needle of 18 or 17 gage (approximately 1 mm or less in diameter) and placement in an annulus that is competent - i.e. retains dye on discogram (other imaging measures can be used as well to make this determination). We have had no reports of extrusion with close to 1000 units of GelStix sold.

Further, the product has been designed to augment the disc as opposed to replacing large volumes of nucleus. The GelStix has been implanted in patients after endoscopic or microscopic discectomy but only after months to years have passed and the annulus has "healed" or at least retains dye and there is no further evidence of herniation.

The product is not designed to be implanted in combination with transforaminal endoscopic lumbar decompression procedures that use endoscopes and create large defects in the annulus. We can not recommend implanting the device through anything other than an 18 or 17 gage needle - 2mm (as far as we know now) is too big because there is the potential to extrude as you have noted below. Also, we see clinical benefits in the patients treated when the device is used as packaged. In this situation, we typically are introducing around 1 cc of implant material. We have no experience with implanting several packages of GelStix and would not recommend doing this at this stage of the product's development.

I hope that this helps us all understand the positioning of the product. Mr. Singh may have tried using GelStix in combination with stem cells in some of his patients so he is copied on this email to shed some light on his experience.

There may be great synergy for the combination but if GelStix is used as currently configured, we need to be mindful of the volumes that are being implanted and must be careful not to introduce too much material or to create a defect that is too large to retain the product under normal pressures.

I look forward to discussing your interest in GelStix further.

Ann Prewett
Director of Research


Letter to Mr Knight,
Actually we have met several years ago; and I believe you were visiting Malaysia about 10 years ago also. I have used your endoscopic equipment. I believe another Mr Knight (from Australia) sold the endoscopic sets in Asia.
I have began (in selected patients-3 to date, as a salvage procedure) to use gel stix in combination with autologous cells (bone marrow derived; CD34+ and CD105+). I avoid the term stem cells as it evokes unnecessary alarming emotional responses in Malaysia; however the term autologous cellular therapy has found favour with our regulators.
I have not been able to fit more that 2 gelstix in the lumbar disc; and only 1 in the cervical disc. Ann has now provided me with a smaller piece for the neck; however I have not yet used it. I believe it would be more suitable for the Asian neck.
Having reflected on your long term, pioneering experience in foraminal decompression; it is my belief that in combination with gelstix; patients with classical DDD would benefit. I will be combining a foraminoplasty with gel stix in the next suitable patient.
Harwant Singh MD FRCS PhD


Letter to Dr. Tanner:

Apologies for late response. I just found your note in my junk mail basket. The Gelstix has been in clinical use for approximately 2 years and we have had consistently very good to excellent outcomes. Dr. Ann Prewett would be the contact person for you concerning future trials at your facility. She is heading the European trial centers of which I believe she is organizing approximately 4 more clincical trial centers.

James J. Yue, M.D.
Associate Professor
Department of Orthopaedic Surgery
Spine Surgery
Yale University School of Medicine

Letter to Dear Dr Tanner,

Briefly, i have used the GelStix for one year in 53 patients to date. The early results of the first 20 patients have been presented at Termis in sept 2012. I attach the programme (pg 48). i have used the procedure in combination (at same sitting) with RF nucleus ablation (nucleoplasty-arthrocare) or with Dekompressor (stryker pain) in lesser number of cases who were diabetic (for fear of infection). I did not see any difference in outcome. The reason i combined it with the nuclues ablation/decompression is purely for third party reimbursement purposes. I believe that the product will be just as effective as a stand alone.

I also attach the references to the intradiscal treatment outcomes that i have presented recently. This gives the background and evolution of my practise and outcomes. The sceptic in me feels that it does not matter what modality of intradiscal treatment is used, the outcomes are similar; largely due to the fact that the VAS and ODI are not sensitive enough to tell the difference. I have noted that universally one sees a pre VAS of between 7 to 8 that will fall to a VAS of between 2 to 4 within the first year (colleagues elsewhere report the same). There is nothing much reported after a year; only what we hear from social talk after a few drinks! However, it has fared well for the patients i see in my practice, and they are generally happy.

My feeling is that the sustained pain relief for these patients beyond a year would come from a nucleus augmentation devise (Gelstix), and as Mr Knight has shown, a foraminal procedure. These would address the major issues of the cascade degeneration in the nucleus; and the attendant osteophyte formation/ facet hypertrophy that one generally sees developing as part of the natural history of disc disease.

Harwant Singh. MD FRCS Phd

Intradiscal References.

1. Lumbar intradiscal treatment:A comparison between 5 modalities (Physiotherapy/Chiropractic, IDET, Dekompressor, Nucleoplasty, Disc-Fx) in 592 cases in a single surgeon's practise. Harwant Singh
World Forum for Spine Research 2012, Helsinki 18-21 June 2012

2. Intradiscal treatments: Is there any difference between mechanichal decompressions and RF ablation of nucleus pulposes (Needle and Endoscopic assisted). Harwant Singh
30th ISMISS. 26-27 January 2012, Zurich.

3. Intradiscal treatments: Is there any difference between modalities? Harwant Singh
28th ISMISS. 28-29 January 2010, Zurich.

4. Intradiscal Treatments: A preliminary report with an evaluation of patient satisfaction. Harwant Singh
27th ISMISS. 29-30 January 2009, Zurich

5. Altering the natural history of lumbar disc disease. Do mechanical Intradiscal Therapies work? A preliminary report. Harwant Singh, Naveed Nayar Wazir, BA Kareem, HK Shong
14th IMLAS Congress. 17-20 May 2007, Langkawi, Malaysia.

MHRA Clearance

I have received clearance from the MHRA to proceed with this as a surgical intervention

Martin Knight MD FRCS MBBS