Good morning, everybody. My name is Jason Shaw. I'm a orthopedic surgery resident at Emory University, and today I'll be discussing a project that our team here completed looking at the projections and epidemiology of total ankle and revision total ankle arthroplasty projected out to 2030. Here are my co-authors listed here. Briefly, we have no relevant disclosures to this topic. So just a brief background, end-stage ankle arthritis causes significant disability and associated significant socioeconomic implications. There's a multitude of manuscripts and papers documenting this, and so it's important to discuss the treatment options. So historically, there are two mainstays of treatment for end-stage tibiotalar arthritis, the first being tibiotalar arthrodesis and the second being total ankle arthroplasty. Historically, looking back at the treatment options, arthrodesis has really been the gold standard of treatment, but it does come with some pitfalls. The most significant being it sacrifices motion at the tibiotalar joint and increases strain on adjacent joints. Even with these pitfalls, it still has been the mainstay. So we look historically, the risk-benefit ratio for arthrodesis has been extremely favorable in comparison to early total ankle arthroplasty. There was high complication rates, early failures, low surgeon utilization, steep learning curves. And so again, historically, arthrodesis was truly the mainstay. And so if arthrodesis has been the mainstay in work, why are we even discussing total ankle arthroplasty? And it kind of goes back to the biggest pitfall is that we sacrifice motion and patients don't like that. And so the newer data that has been well documented shows that there's significant improvements in the clinical outcomes with the modern technology, fellowship, surgeon, learning, education, as well as the implants themselves. And it demonstrated that at five years, the total ankle arthroplasty has a comparable survivorship to total ankle arthrodesis. And this has been studied in a multitude of different investigations, which have demonstrated similar outcomes. And so the thought currently is that these improved outcomes, improved learning curves, and improved technology has really led to the exponential growth in the utilization of total ankle arthroplasty. And so what does our study want to look at? So there are many studies that have retrospectively looked at the increase in total ankle arthroplasty and revision total ankle arthroplasty, but there's really no data looking at the projections of where are we headed, right? So what do we expect to see 10 years from now in terms of volumes of total ankle arthroplasty and revision total ankle arthroplasty as this truly is a relatively new field? And so the aim of our study is to utilize a national database looking at total ankle arthroplasty and revision total ankle arthroplasty and predicting long-term trends, including epidemiologic specifics of both primary and revision arthroplasty to the year 2030. So briefly our methods, we utilize the National Inpatient Sample Database, which is a well-documented database that's been published on numerous times and has had its validity confirmed by numerous studies. We identified patients from 2005 to 2017 using the ICD-9 and 10 codes listed below, identifying total ankle arthroplasty, revision total ankle arthroplasty, and then septic revision total ankle arthroplasty. Statistical analyses. So we, again, looked at trends from 2005 to 2017, utilizing a progression log function and using 0.05 as our level of significance in a two-sided t-test. For our predictions itself, we use two models, one a linear model, one a Poisson model, looking at the predictions to 2030. And the Poisson model was chosen for this, as it's been well-documented in actually the arthroplasty literature, showing quite significance in relation to kind of exponential growth in the learning field. And it gives us two models to kind of, one that we will describe as more of a conservative model, and another one as an exponential or a more aggressive model in kind of predicting our total case volumes. So looking at our results now, just briefly looking at it, for primary total ankle arthroplasty from 2005 to 2017, we went from 800 cases identified to 5,315 with a 564% increase. Looking at aseptic provision, total ankle arthroplasty went from 459 to 1,170, 154% increase. And then looking at septic revision, total ankle arthroplasty went from 189 in 2005 to 705 with a 256% increase. Across the board, these were all significant with a p-value less than 0.001. Now looking at subgroups. So initially, first looking across the board at males, from 2005 to 2017, we saw a significant increase in all three primary revision and septic revisions. Interestingly, only the primary total ankle arthroplasty had a significant increase in our female subgroup. Looking at our subgroup analysis by age, we saw that from 45 to 75, greater than 75, we had a significant increase in the incidence of primary total ankle arthroplasty, but the greatest increase was actually seen in our 65 to 74-year age group. Looking at revision total ankle arthroplasty, our significant data set showed that from 45 to 74, we had the greatest increase in revisions for aseptic indications. And then interestingly, there was actually no significance when looking at subgroup analyses for the incidence of septic revision total ankle arthroplasty across the board. So now looking at our models, looking at our projections. So looking first at the projected volumes of primary total ankle arthroplasty, so focusing first on our linear model, we see 110% increase by year 2030, with our POISSON model predicting a 796% increase. So again, really falling on our exponential growth curve as we really may see surgeons sort of using this more and more than tibial tail or arthrodesis. Again, both these values were significant when compared to the values at 2017. Now looking at our aseptic revisions. So again, using our linear model first, our conservative model predicted a 45% increase in aseptic revisions with 141% in our POISSON model. Again, we had a significant increase with our POISSON model, but not a significant increase in our linear model. So again, looking at our projections, looking at septic revisions, again, 22% and 120%. Again, a significant increase of our POISSON model, but not a significant increase in our linear model. So why does this matter, right? So our analysis is the first to demonstrate a significant increase in the utilization of total ankle arthroplasty, right? And our models predict that we should expect a significant increase in the use of total ankle arthroplasty. What is important to note is that we also demonstrate an increase in the rate of septic and aseptic revisions. And that's something that surgeons and patients should consider as revision total ankle arthroplasty do come with implications and have quality of life factor adjustments. And so it's something that both the surgeon and patients should be aware of prior to proceeding with a total ankle arthroplasty, those consequences can be quite significant. And so the real main take-home point is that these findings kind of should give both surgeons and patients caution, right? We should do more research into refining our surgical indications of total ankle arthroplasty. We should do a better job of providing protocols for revision total ankle arthroplasty, similar to what the adult reconstruction folks have done with both hip and knee replacements. And it also puts some pressure on the technologic advances of our implants, right? We should be scrutinizing our implants, our failure rates, as well as revision rates. And it's something that we should consider greatly when signing a patient up for surgery. And so we hope that this dataset really provokes people into thinking and doing some prospective research into the rates of revision total ankle arthroplasty, developing these revision protocols, and really should help put a spotlight on this, as we do really expect quite a significant increase in the incidence of total ankle arthroplasty. And so with that, I thank everyone for their time and appreciate it, and we'll be more than happy to take any questions.

Dr. Jason Shaw

Emory University

total ankle arthroplasty

revision ankle arthroplasty

epidemiology