Dr. Guyer - CDR

Speaker 1OK, Doctor G Guyer, let's turn it over to you.

Speaker 2All right, hope I, I can see my slides. Well, listen, I, to follow Roger and to Dom, it's really a hard, uh, play, but I promise you I'm not gonna talk about foraminotomy and I'm not gonna talk much about fusions.

Speaker 1Next

Speaker 1slide. And, uh,

Speaker 2sorry, I don't have my disclosures, but I do, uh, consult for a number of cervical arthroplasty companies. So the question is, what's the best option for this patient? Next slide.

Speaker 2And as Dom ended up, there really isn't a bad option and unfortunately, the decision is oftentimes made on the biases of the surgeon's experience of the various techniques, although I do agree that you should be fossile on all three.

Speaker 2But in most areas of Spine, there's more than one acceptable treatment option and rarely is it black and white. And until we have more data, registries and predictive analytics, our decision making will be primarily based on the first point that is based on your experience and your biases. But I am here to talk about cervical arthroplasty, so I am going to, uh, try to defend why this is a great choice, whether it's workman's workman's comp or

Speaker 1not. So next slide.

Speaker 1So

Speaker 2coming from the orthopedic background, uh, in 2020 there's been a trend towards preservation of motion.

Speaker 2And MIS techniques. So, for example, if, if Dom or, uh, Roger had a bad Hip and, uh, you went to see the Hip surgeon and he offered you a fusion, would you really, would you accept that? Would you say, isn't there something better? Next, next click. So, obviously, nobody today undergoes a Hip fusion or a Knee fusion.

Speaker 2Even in the face of infection. Next slide. So the same holds true for the neck. When we have the options of doing motion preservation, and yes, foraminotomy does the same, why would we offer the patient a fusion, even though Dom has very well showed that most motion comes from the upper level and maybe it doesn't cause any problems. Next

Speaker 3slide.

Speaker 2So as Dom said, cervical arthroplasty has long been considered to be the gold standard, but there's been no area in Spine, and I mean no area in Spine, in all of Orthopedics, and I venture to say even a neurosurgeon, although not as knowledgeable about your literature, there's been no area where there's been multiple RCP RCTs and has been consistently found that TDR results are similar or superior to ACDF.

Speaker 2Next.

Speaker 2So it's winding creeping up and this somebody needs to mute this uh microphone. But anyway, so here's the Hildebrand article and, uh, but the real problem with ACDFs are that you have a problem with plates, you have a problem with pseudoarthrosis, you have a problem with subsidence of the graph and with migration of the screws into the next level.

Speaker 3Next.

Speaker 1So we have 8

Speaker 2completed FDA trials thus far, and all the data is available in the public domain domain.

Speaker 2We, all of them are prospective randomized level one trials comparing TDR to ACDF all with one level and two discs having two-level

Speaker 1data.

Speaker 3Next,

Speaker 1there's many, many

Speaker 2different artificial discs. One of the nice artificial discs that Dom showed in one of his cases that didn't, that went on to an auto fusion is the Brian disc. But you see listed here, these are the 8 approved discs. The ones in red have been taken off the market because now we have more modern discs, and the most recent one was the Viscolastic disc.

Speaker 2Dic, which is the M6, which not all artificial discs are the same. The M6 disc actually has a center axis of rotation and lateral bending and flexing extension, very similar to the normal Spine, whereas the others are basically ball and socket or sliding. Next, we also see that there's a number of Other studies that have been done. Dom and I were co-PI on the simplified 1 and 2 level, and we're hoping to get approval or see approval at the end of 2020 and early Q1 for the two level.

Speaker 2Sentinel is also doing a study on their European available discs that we don't have here, the synergy disc that is coming from Canada, the Diamondron, which is made out of a unique diamond material with unique surfaces, and the spinear Baara C. These are future studies. Next.

Speaker 2And then we have a number of studies that didn't come off. Dom and I were KPIs on the Kiflex, which a metal metal, which unfortunately, uh, went the way by the wayside like all metal model implants, even in the hips and knees. And then we see another, uh, several artificial discs that didn't make it, and many of them we saw before that showed failures.

Speaker 3Next.

Speaker 3Um,

Speaker 2currently, these are available outside the US. Uh, there's a couple Visco Leia discs. One is the, uh, Freedom disc, and the Other is the RIM.

Speaker 1Next.

Speaker 2But if you look at the number of publications and, in the, um, and I don't know if it shows up real well, but in the, the red outline, uh, bars we see in 2017, there are a huge number of discs now published.

Speaker 2On cervical arthroplasty.

Speaker 3Next,

Speaker 2and all the single-level trials found the TDR to be non-inferior to ACDF and superior in some measures, and the results have been maintained up to 10 years with long-term follow-up now available in 3 of the studies.

Speaker 3Next, and

Speaker 2if we look at the NDI scores and granted this has TDR and ACF, but remember these studies were compared.

Speaker 2And we see after 10 years and we have, uh, and it's kind of small for us to read, but uh the 3 lines after 10 years are the artificial disc and we see that the improvement of the NDI is maintained after 10 years.

Speaker 3Next,

Speaker 2and what this shows is that the data is very, very reproducible across multiple devices in all these multi-center trials.

Speaker 1Next.

Speaker 2And also we have data from multiple Other countries that show the results um are um and are the results are never less favorable compared to

Speaker 1the ACDF

Speaker 3that

Speaker 1we also

Speaker 2see um.

Speaker 2And um in this study that uh with 330 some cases follow up at 5 years that there's only 4.5% revision in the arthroplastics

Speaker 3next.

Speaker 1And in this

Speaker 2meta-analysis, uh, they showed that TDR had a lower reoperation rate, a lower reoperation rate for adjacent level when analyzed, utilizing this fixed effect, uh statistical model, but not according to the random

Speaker 1effects model.

Speaker 3Next,

Speaker 2and we have 10-year follow-up now from, uh, the Brian, the Prestige, the MobyC and overall, the Brian showed that the success rate at 10 years was 81 versus 64%.

Speaker 2The adjacent level reoperation rate, although it was not statistically significant, was 9.7 versus 15.8, and the range of motion was maintained, and this is a disc that's now been taken off the market but still has withstood the test of time.

Speaker 1Next,

Speaker 2and in the Prestige LP, which is a currently used, um, disc as well as the MobiC.

Speaker 2Both found significant improvement in early pre-op maintained through 10 years and lower reoperation rates compared to their fusion

Speaker 1cohorts.

Speaker 3Next. Next.

Speaker 2And when, uh, looking at real-world data that is non, uh.

Speaker 2Randomized observational studies compared with the RCTs this in this, uh, study, they found that there's no difference in the treatment effects between observational, in Other words, what people are publishing outside of the IDs and the RCTs, so the data remains pretty firm.

Speaker 3In

Speaker 2addition, we want to maintain motion and, uh, as Do alluded to, of course, I'm gonna show this. So let's see the next

Speaker 1slide.

Speaker 2And if we see tabulated here all the different artificial discs and not all the data is available for everyone, but we see that basically, uh, the data, the range of motion is maintained at least after the seven-year follow-up, and we have a couple out to the 10-year.

Speaker 1Next.

Speaker 2And what about adjacent segment degeneration? You know, it's the old story is that.

Speaker 2Um, you know, just natural history or is it increased stress based on what we're doing to that level, and you know, the holy grail is that the artificialness should produce less stress and strain, and biomechanically this has been shown.

Speaker 2Uh, literature generally supports it, but not all studies do.

Speaker 3Next,

Speaker 2so in this study, this was a, um, meta-analysis that looked at 20 studies over 3800 patients, uh, 2000 were fusion and 1500 were ACDF, and they concluded that there's a lower probability of ASD reoperation with TDR after 60 month followup compared to the fusion.

Speaker 3Next.

Speaker 1This is a study

Speaker 2where Dom was the lead author on, and this showed that in 2 years with our metal metal kineflex disc, it actually had very good data except for the problem with metal metal uh problem showed that there's a greater percentage of patients that had degeneration circled by the little red circle at 2 years compared to the TDRs which maintain the same levels as pre-op and post-op.

Speaker 3Next.

Speaker 3And

Speaker 2this comes from the MoBC data. It shows adjacent level Surgery rates through 60 months. We see that the one and two level MoBC on the left, uh, were relatively small at 2 and 3+% compared to 11.4% for the, um,

Speaker 3fusion

Speaker 2patients. Now this is a published, uh, paper from, uh.

Speaker 2A group that had participated in a number of IDE studies and they looked at their patients and what they found was that uh for single level patients the adjacent segment reoperation was 4.3% versus those of fusion, uh 15% in the two levels 5 versus 12

Speaker 2next.

Speaker 3And uh

Speaker 2in this study, again it was a meta-analysis and they found that TDR had significantly lower secondary Surgery rates of 5.8% versus uh greater than 11% for fusion patients. That is impressive

Speaker 1currently.

Speaker 3Next.

Speaker 2And also, um, Speedback had published a paper looking at the uh the adjacent level disease or radiographic changes based on the range of motion, and this included both fusion and TDR patients. Obviously, fusion patients are going to be grouped with the 0 to 3 degree.

Speaker 2And, uh, as we see greater range of motion, we see less chance of adjacent segment radiographic changes, uh, when it's greater than 7 degrees of

Speaker 1motion.

Speaker 3Next,

Speaker 2it's sort of, it's a little fuzzy because it, it also includes some of the adjacent levels, but every operation is obviously, you know, doted, you know, you have to salvage an artificial dish, you got to do another operation, do a fusion. So let's look at some of the data there

Speaker 1next.

Speaker 2So this was a

Speaker 2study, uh, based on six prospective randomized IVE trials that we published and we looked at our 84 disc replacements in 52 ACDF patients with a mean followup of about 4.5 years. Next, and our reoperation rate was about 8.2% for the TDRs and 21% for the ACDF, which was significant to be less than 0.05.

Speaker 1Next.

Speaker 2And Other studies

Speaker 2report a similar low reoperation rate with TDR compared to ACF, but none ever showed a higher rate of reoperation compared to the TDRs.

Speaker 1Next,

Speaker 2and this is subsequent Surgery rates coming from the MoBC data and, uh, what they showed was 3 and 4% for the uh.

Speaker 2For the OBC and for the ACDF it was upwards of 11 to 16% for the two level fusions that is next, so a potential shortcoming Don mentioned was heteroopic ossification and.

Speaker 2Um, as he said, what happens is the patient in some cases may turn into a fusion, but not all cases. So let's look at the data

Speaker 2next.

Speaker 2So the reports vary according to different studies, anywhere from 16 to 85%. There's several factors, and we're not sure really what caused it. Is it the operative technique? I used to think it was from the milling, but we see it with all different, uh, designs.

Speaker 2And is it the patient characteristics? We don't know, but now we put the patients on a two-week course of anti-inflammatories after Surgery. This is purely anecdotal. We'll have data hopefully within the next year or two when we look at our

Speaker 1data. Next.

Speaker 2So in this study, they looked at 38 cases and they looked at the amount of HO after, uh, these various time frames. So let's show, show the

Speaker 1next slide.

Speaker 2And they didn't grade it Other than moderate or up to the severe level, and we see that at all time frames we see increasing rates, so.

Speaker 2You know, although they didn't grade it according to the typical grades of grade 123, and 44 is a complete fusion. 3 looks like it bridges, but there's still motion. Grade 1 is a little bit of bone and grade 2, they still have normal motion. So obviously out to greater than 7 years, you're going to see a high amount of, uh, HO.

Speaker 3Next.

Speaker 1And,

Speaker 2uh, this was the Bryan study with a follow up of 94 months

Speaker 3next

Speaker 1and.

Speaker 2HO was 50%, but again they concluded that there was, it didn't affect any negative outcomes and there's still significant improvement even with the patients with and without HO and they felt the patients that had more preoperative spondylosis had higher rates, um, and also with adjacent segment degeneration

Speaker 1next,

Speaker 2so, uh, in this, uh, sort of concluding, uh, data, it showed that.

Speaker 2Basically, the pre-operation rate of TDR was superior to ACDF. Regarding radiographic outcomes, no firm conclusion could be drawn from the TDR infusion. TDR did decrease the rates of adjacent segment radiographic changes as well as disease compared to ACDF. Uh, multilevel TDR may be effective and a safe alternative to HCDF.

Speaker 2And the one level TDR offers similar outcomes with a low reoperation rate and also versus the cost of ACDF. And although the data regarding the two level is less robust, they may be as effective as the one level TDR data. Next.

Speaker 2So we, we're now seeing that level level one data with 10 year follow up from multiple perspective studies, and we've never seen anything like this for fusions, uh, for cages, for plates, uh, that we have, uh, even for the various graph materials, and the successful results early are being maintained after 10 years.

Speaker 3Next,

Speaker 2so we're not seeing as a significant of the TDR failures, although Do did show us one.

Speaker 2Uh, there's no reported, uh, publication showing that TDR produces inferior results to ACDF based on the clinical outcomes or re-ops, and the TDR unfortunately may be close to the new gold standard for the typical cervical radiculopathy without all the Other contraindications. Next, so like this 36, uh, so like my 36 year old patient.

Speaker 2Um, that we did a, a TDR had exactly the same picture and especially for my 46 year old patient that had a previous fusion, the TDR was an excellent option for them. So basically for this patient, even

Speaker 2though next

Speaker 2he was work comp in Texas, we don't get paid a lot of money for work comp, so therefore we can be very.

Speaker 2Very selective and have them go through psychological screening and pick our patients very well. I think that TER is one of the, with one of the newer implants, not one of the older implants, is an ideal solution. But as stated before, all the options are good for this patient. I, I don't think that any of them are a bad option.

Speaker 3Next. Thank you.