Good afternoon. My name is Megan. I will be your conference operator today. At this time, I would like to welcome everyone to Nevro's Q3 2021 Financial Results Conference Call. All lines have been placed on mute to prevent any background noise. After the speaker's remarks, there will be a question and answer session. If you would like to ask a question during this time, simply press Star followed by the number one on your telephone keypad. If you would like to withdraw your question, press the pound key. Thank you. I would now like to turn the call over to Julie Dewey for introductory remarks. Please go ahead, ma'am. Good afternoon, and welcome to Nevro's Q3 2021 Earnings Conference Call. We appreciate you joining us. I'm Julie Dewey, Nevro's VP of IR and Corporate Communications. With me today are Keith Grossman, Chairman, CEO, and President, and Rod MacLeod, Chief Financial Officer. The format of our call today will be a discussion of third quarter business results from Keith, followed by detailed financials and guidance from Rod, and then we'll open up the call for questions. Please note there are also slides available related to our third quarter performance on the Nevro investor relations website on the Events and Presentations page. Earlier today, Nevro released its financial results for the third quarter ended September 30th, 2021. A copy of our earnings release is available on our investor relations section of our website at nevro.com. This call is being broadcast live over the internet to all interested parties on November 8, 2021, and an archived copy of this webcast will be available on our investor relations website. Before we begin, I'd like to remind everyone that comments made on today's call may include forward-looking statements within the meaning of federal securities laws. Our results could differ materially from those expressed or implied as a result of certain risks and uncertainties. Please refer to our SEC filings, including our Form 10-Q, to be filed today, for a detailed presentation of risks. The forward-looking statements in this call speak only as of today, and we undertake no obligation to update or revise any of these statements. In addition, we will refer to adjusted EBITDA, which is a non-GAAP measure that is used to help investors understand Nevro's ongoing business performance. Non-GAAP adjusted EBITDA excludes certain litigation expenses, interest, taxes, and non-cash items such as stock-based compensation and depreciation and amortization. Please refer to GAAP to non-GAAP reconciliation table within our earnings release. Now I'll turn the call over to Keith. Thanks, Julie. Good afternoon, everyone, and thank you for joining us. I'll focus my comments today on our third quarter results, the current state of our business and COVID recovery, and on our PDN launch. Following my comments, Rod will cover specifics of our third quarter results and our fourth quarter guidance. In the context of the current COVID environment and the related headwinds, we're still pleased with our third quarter results, which were at the high end of the guidance range we communicated in August. Both U.S. and international revenue were impacted by the Delta variant surge and other COVID-related issues, including patient behavior regarding elective procedures, healthcare facility restrictions, and staffing shortages. As a reminder, after the deep impact of COVID in the second quarter of last year, we regained our canceled or backlogged patients and recovered revenues considerably faster than all of our competitors last year in Q3, giving us a challenging 2020 Q3 comp as a result. In fact, if you look at the quote, unquote, "net recovery impact," and for us that means canceled cases from prior quarters that were recovered in the current quarter minus the impact of new case cancellations in the current quarter. We enjoyed a net recovery impact of approximately $14 million to revenues in the prior year third quarter. While our net recovery impact this year was roughly a -$1.6 million to revenue, or roughly fifteen million dollars swing on a year-over-year basis. Now, you'll see a table on that impact in our summary slides that were just posted on our investor website. Compared to the third quarter of 2019, we delivered strong third quarter adjusted EBITDA results, demonstrating our ability to continue to improve efficiencies in the core business despite investing in new growth drivers like PDN and NSRBP, as well as our new manufacturing capability in Costa Rica. Rod will cover expense efficiency trends in just a few minutes. We continue to be really excited about the PDN opportunity, which I'll discuss in more detail momentarily, and we're confident that we're well positioned for attractive core market growth when the impact and uncertainties of COVID on our market completely subside. Now, I'd like to look at actual procedure activity. Compared to prior year, Q3 total U.S. permanent implant procedures decreased 14%, while trial procedures decreased 7%. Now, remember that the same comparable issue I outlined for revenue impacts year-over-year, procedures, impact year-over-year re-procedures as we were recovering a lot more canceled cases in the prior year third quarter. Encouragingly, however, our monthly trial and permanent implant procedures improved steadily over the course of this quarter, and that trend has continued into the fourth quarter thus far. Compared to the third quarter of 2019, U.S. permanent implant procedures decreased 8%, and trial procedures decreased 9%. Trial and permanent implant volumes were also still impacted by a continued reluctance of new patients to seek interventional therapies for chronic pain in numbers comparable to pre-COVID levels, as well as scheduled case cancellations and elective procedure capacity constraints due to COVID concerns, customer capacity, and labor constraints. Of course, trials drive future permanent implants and revenues. Current trial procedures are certainly a primary driver of our Q4 guidance. On our last quarter call, we provided a significant amount of market, physician, and patient research data to explain the slower SCS market recovery. I won't repeat that data again here today, except to say that nothing has substantively changed. We believe that patient reluctance to reengage and willingness to defer is still a significant issue behind the slow SCS market recovery. Fortunately, this factor is showing signs of improving, though in our view, the impact of center capacity constraints related to labor shortages has probably grown. Importantly, we have still uncovered nothing to indicate that there is any enduring or fundamental change to or problem with the SCS market beyond the pace of COVID recovery. As I've said, we believe Nevro continues to perform well relative to the overall market by almost any measure. In addition to the research that we did last quarter, our team also completed some additional survey work with patients and physicians, which confirmed that these previous findings are still valid. Clearly, the markets for chronic pain treatment remain among the more deferrable elective care areas by patients. You'll recall on our previous survey that the primary reasons patients said they were reluctant to seek care were financial issues and ongoing fear of COVID. In our most recent survey work, we found patients are still reluctant to seek care due to financial and economic reasons, but their ongoing fear of COVID has have decreased substantially. This continues to support our belief that the revenue impact and slower SCS market recovery is temporary, and that these patients, while still suffering from unresolved chronic pain, are nonetheless more able and willing to defer their treatment than patients in some other elective care categories. Pain doctors and primary care physicians continue to tell us that they anticipate patient volume returning, and our pain doctors almost uniformly confirm that they remain very interested in SCS therapy and are looking to grow their SCS business going forward. On the topic of timing, an equal three-way split of pain doctors feel that the recovery will accelerate this quarter. Some see the recovery coming early next year, and still others who see a recovery pushed into the second half of 2022. Finally, from a relative performance standpoint or share of market, we continue to see high variability in quarter-to-quarter results among market participants, though year-to-date, we feel like we've continued to win in a difficult 2021 market. For the first three quarters of 2021, our U.S. revenues were up 4% compared to 2019, while we believe the U.S. SCS market was down approximately 3%. In fact, we believe we're the only company well into positive year-to-date growth in the U.S. versus 2019. As we look at actual year-to-date procedures in 2021 versus the same period in 2019 by using claims data, our U.S. trials were down 5% year-to-date, while total market SCS trials were down 11%. Our U.S. permanent procedures were up 4%, while total market SCS permanents were down 8%. Let me close this portion of my remarks by concluding that we're finally allowing ourselves enough optimism to conclude that the worst of the COVID impact on our business may be behind us. Patient and physician interest in pain treatments remains high, and after a very tough 18 months of COVID, we saw the first green shoots of recovery with a steady pickup in trial activity that occurred within the third quarter and in the fourth quarter thus far. In fact, we continue to believe we're well-positioned for longer term attractive growth in our lower back and leg business when the full impact of COVID on our market subsides. In addition, we're excited to now provide the only SCS treatment option approved by the FDA for patients who are struggling with debilitating PDN, or painful diabetic neuropathy, and who are unable to find relief with currently available drug options. Following the FDA approval of Nevro's proprietary high-frequency, or HFX for PDN in July, we began U.S. commercial launch activities in earnest. While still, of course, in its infancy, the first three months of this launch have reinforced our excitement about our PDN indication and how impactful we believe this will be for providers and patients. We're very encouraged by the high levels of interest among referring physicians and patients, early trial volumes, and the validating clinical outcomes in those patients who have already received their permanent implant. Worldwide PDN revenues for Q3 was approximately $1.7 million. In the quarter, we performed 175 PDN trials and 71 PDN permanent implants in the U.S. In September, the second full month of our launch, PDN trials already represented approximately 6% of our total U.S. trial volumes, and we're on track for a meaningful increase in the number of PDN trials in Q4 over Q3. We will continue to provide you with this PDN trial information during the early phase of our PDN launch, but for a variety of reasons, we may or may not provide this level of detail in perpetuity. Through October, we've generated over 20,000 qualified PDN patient leads with our DTC advertising and PDN-specific patient campaign. Our HFX coaches have proactively reached out to a subset of these patients, and the first several hundred of these DTC leads have been handed off to our U.S. sales team. Our new PDN referral sales team has called on close to 6,000 referring physicians and generated over 500 patient referrals to SCS specialists. We're finding the unmet needs of these patients are truly top of mind with the referring clinicians, and many times we've been entrusted with patient referrals on the very first sales call. Among our early treated PDN patients, we're seeing the results that we would expect based on our clinical trial outcomes, and we're working with the referring doctors to make sure they're well aware of the very positive results with their patients after the fact. Also encouraging is that our core SCS sales team calling on our existing pain specialists is gaining access to new competitive accounts that didn't previously implant or use Nevro products. PDN is opening doors for us with these customers, and many have already begun using Nevro, not just for PDN, but for lower back and leg patients as well. This demonstrates that our customers understand that treating PDN with high frequency therapy is exclusive to Nevro, thus providing unique efficacy to an entirely new category of patients. We feel at this point we're getting credit from customers for the investment we've made in our technology, in our clinical trial and FDA approval, and in the generation of a new stream of referrals to their practices. We've also seen tremendous willingness among our pain specialists to reach out to referring physicians in their local communities and even to do their own patient outreach. We've seen TV commercials, physician website updates, billboards, news stories, education events, social media posts and more from our customers regarding the ability to now treat PDN with 10 kilohertz therapy in their practice. We've executed 52 PDN expert seminars for pain physicians, ensuring that these doctors are educated not only on how to treat PDN patients with 10 kilohertz therapy, but also how to achieve the significant clinical outcomes we reported in our trial. We've received significant press attention in the pain community, but also with diabetes advocacy groups such as Beyond Type 1 and DiabetesMine. We've submitted our 12-month PDN data to a top-tier journal and anticipate that these results will now be published as early as late this year. We're hopeful that these published results, along with our robust clinical dossier, will support expansion of coverage policies to exclusively cover 10 kilohertz therapy for PDN. In addition, the health economic analysis of the six-month data has been accepted as an abstract at the International Society for Pharmacoeconomics and Outcomes Research, or ISPOR, one of the world's leading health economic conferences. These data will be presented during their upcoming virtual European conference taking place this year from November 30 to December 3rd. We'll compare healthcare resource utilization data consisting of hospitalizations, ER visits, medication use, and other outpatient services between the high frequency therapy and conventional medical management arms. We also plan to submit the health economic data for publication later this year, analyzing the long-term outcomes of PDN patients treated with our proprietary 10 kilohertz therapy. Together, these data will be used to support physician referral decisions as well as market access initiatives to expand payer coverage of this procedure. Now, with regard to payer coverage, we're continuing our work and outreach to the payer universe to expand market access and drive adoption, which of course is a process that takes time. We have two key strategies to achieve this, which are first developing HFX-specific positive coverage policies for PDN with our payers. Concurrently, we're using our dedicated team of 20-plus reimbursement specialists in our HFX Access group to assist with obtaining individual prior authorizations on a case-by-case basis where we've already seen some good success. Keep in mind that each payer has its own SCS policy review timeline, effective date, and may even collaborate with a third-party administrator to manage their coverage policies. With this in mind, we expect our payer coverage to increase gradually over time with a steady increase in coverage occurring throughout 2022 and beyond. We continue to anticipate a mid-single-digit million dollar revenue contribution from PDN in 2021, with broader penetration and a larger revenue contribution expected in 2022 and beyond. The revenue ramp is expected to build gradually during these initial launch months as patients move through the referral to trial to permanent implant pathway, but also as awareness increases among referring physicians and patients and access with payers expands. We're generating awareness with patients and physicians for a brand-new PDN treatment option. It's gonna take some time for treating physicians to identify these patients. Of course, some physicians may refer one patient, then wait to see results before referring more. For patients, the pathway from referral to trial to permanent implant typically takes months, not weeks. In summary, our launch is still very early, but the first three months have reinforced our excitement about our PDN indication and how impactful this will be for providers and patients. We're looking forward to continuing to develop this exciting growth platform. Our PDN approval is the latest example of how we continue to lead in innovation. Following the acceptance of our PMA supplement submission for NSRBP at the beginning of August to add explicit label claims for these patients, the FDA has now completed the substantive review of our submission. Thus, we believe we're on track for an FDA approval maybe by the end of this year, or if not, in early 2022. We continue to develop the nonsurgical portion of our market using NSRBP data as well and look forward to publishing and presenting our 12-month follow-up data later this year or sometime in Q1. I'd now like to provide some commentary on our recent patent trial with Boston Scientific in Delaware. This trial was a result of a retaliatory suit regarding the design of certain leads that Boston Scientific filed against us in 2016 after we sued them to keep them from launching a high-frequency product and infringing our high-frequency patents, an effort that, of course, has been successful. After five years of litigation, only six of the original 249 claims Boston Scientific asserted against us actually made it to trial. In that trial, the jury found that Nevro infringed four of those six claims across just two Boston Scientific patents directed to ways of manufacturing SCS leads, which Nevro obtains from a third-party supplier. The jury awarded Boston Scientific $20 million in damages, and we obviously disagree with the outcome and will now proceed to appeal the findings of infringement of those four claims. However, it's important to remember that the technology at issue in this trial was unrelated to our innovations in high frequency, has no bearing on Nevro's commercial strategy for any of our current or planned products, or our continued exclusivity of 10 kilohertz therapy. The jury award itself is an amount of money that will have no material impact on our business, and was, by the way, far less than Boston was seeking. This was likely Boston's best offensive opportunity in our view, and it fell well short of being impactful, and we feel very good about where we stand going forward in the litigation matters that remain. In closing, we continue to believe we are very well-positioned for longer term attractive growth when the full impact of COVID on our market subsides, a process that we're now becoming optimistic has begun. Our early PDN launch is really exciting. Our fundamentals remain intact, and I believe we're well set up for 2022 and beyond. With that, I'll pass the call over to Rod to provide further details on our third quarter results and our guidance. Thanks, Keith, and good afternoon, everyone. I'll begin with our worldwide revenue for the third quarter of 2021, which was $93.2 million, a 14% decrease, both as reported, as well as on a constant currency basis, compared to $108.5 million in the prior year period, and a decrease of 7% compared to the third quarter of 2019. As a reminder, this quarter included the same number of selling days as Q3 2020, Q3 2019, and Q2 2021. As Keith mentioned, we had a tougher comparable in Q3 2020 relative to our competitors due to the faster recovery of our canceled cases after the initial COVID shutdowns in April of 2020. On a year-over-year basis, this factor represented a swing of approximately $15 million in revenues. U.S. revenue in the third quarter of 2021 was $78.1 million, a decrease of 14% compared to $90.9 million in the prior year period, and a decrease of 7% compared to $84.2 million in the third quarter of 2019. International revenue was $15.2 million, a decrease of 14% as reported, or 16% constant currency, compared to $17.5 million in the prior year period, and a decrease of 5% as reported, or 12% constant currency, compared to $15.9 million in the third quarter of 2019. Similar to the headwinds seen in the U.S., international revenues continued to be impacted by COVID-related issues as well, including both patient behavior and healthcare facility restrictions. Gross profit for the third quarter of 2021 was $64.6 million, a decrease of 15% compared to $76.1 million in the prior year period, and a decrease of 8% compared to $69.9 million in the third quarter of 2019. The decrease in gross profit compared to the third quarter of 2020 was primarily attributable to decreased revenue. Gross margin decreased to 69.3% in the third quarter of 2021 compared to 70.1% in the prior year period and 69.8% in the third quarter of 2019. During the most recent quarter, we continued to invest in our Costa Rica manufacturing facility, which decreased margin by about 130 basis points. We're still targeting shipping product from Costa Rica in the first half of 2022. Operating expenses for the third quarter of 2021 were $111.1 million, which includes a reserve for the $20 million judgment against us in the recent Boston Scientific patent trial. Excluding that judgment, operating expenses were $91.1 million, a 14% increase compared to $79.6 million in the prior year period, and a 6% increase from $85.9 million in the third quarter of 2019. Looking at operating expenses year-over-year, excluding the legal judgment, the increase was primarily related to patent litigation-related fees, PDN marketing, and selling-related activities, and travel and meeting expenses, partially offset by a decrease in personnel costs, as well as management's continued initiatives to drive leverage throughout the business. Litigation fees and PDN expenses accounted for $11.6 million of the year-over-year increase in operating expenses and accounted for $11.9 million increase in operating expenses relative to 2019. Absent all litigation related and PDN expenses, our operating expenses would actually be less than 2019 by almost $7 million or 8%. Legal expenses associated with patent litigation fees were $6.5 million for the third quarter of 2021 compared to $2.3 million in the prior year period and $1.9 million in 2019. Last week's patent trial against Boston Scientific, which Keith mentioned earlier, is one of several ongoing disputes relating to spinal cord stimulation technologies. While Boston Scientific's allegations against us are unrelated to our High-frequency therapy, it's important that we continue to defend ourselves, and it's important that we continue to protect our innovations and paresthesia-free SCS therapy. Net loss from operations for the third quarter of 2021 was $46.4 million or $26.4 million excluding the $20 million litigation judgment. This is compared to a loss of $3.5 million in the prior year period and a loss of $16 million in the third quarter of 2019. Non-GAAP adjusted EBITDA for the third quarter of 2021 was a -$6.0 million. Compared to a positive $13.6 million in the prior year period and -$2.0 million in the third quarter of 2019. We continue to focus on cash preservation while balancing the need to reinvest in the recovery process and our new growth drivers in PDN and NSRBP. Cash, cash equivalents and short-term investments totaled $376.6 million as of September 30, 2021. This represents a decrease during the third quarter of 2021 of $20.9 million, which was primarily due to cash used in operations. Now turning to guidance. It's important to note that we'll be using non-GAAP financial measures to describe our outlook for the business. Please see the financial tables in our press release issued today for GAAP to non-GAAP reconciliations. We expect fourth quarter of 2021 worldwide revenue of approximately $94 million-$98 million. This guidance represents an 11%-14% decrease over prior year and a 14%-18% decrease compared to Q4 of 2019. This outlook assumes some progress in trials and procedure recovery during Q4 as Delta pressure shows signs of easing while also reflecting caution regarding near-term staff shortage issues. We expect fourth quarter of 2021 non-GAAP adjusted EBITDA to be approximately -$10 million-$13 million. We continue to expect a mid-single-digit million-dollar revenue contribution from PDN in 2021, the majority of which is expected to be generated in the fourth quarter, with broader penetration and a larger revenue contribution expected in 2022 and beyond. Keep in mind that our fourth quarter guidance provided today is highly sensitive to the pace of COVID recovery and patient willingness to seek elective care, which continues to be difficult to predict. If these assumptions differ from the actual pace of COVID recovery and its impact on the company's markets, then the company may need to change or withdraw this guidance in the future. With regard to 2022 guidance, we would expect to provide at least Q1 guidance on our earnings call in February, and we'll assess whether or not we have adequate visibility to provide full year guidance at that time. Today, we'd like to provide you with some thoughts to keep in mind as you update your models for 2022. As you are well aware, the SCS market recovery has been particularly impacted by COVID-related issues and has lagged other elective procedures. As Keith said, we are growing more optimistic that the worst of the pandemic may be behind us, and we expect a measured pace of recovery to continue in Q4 and throughout 2022. Keep in mind that there still could be some volatility in the pace of recovery due to the impact from the lower Q3 trial procedures and the difficulty in predicting exactly when patients that have continued to defer SCS treatment during COVID will start to return. Also, keep in mind what we noted earlier in the call that about one-third of our pain doctors see a recovery beginning this year. About a third see the recovery early next year, with the rest seeing a recovery in the back half of 2022. At this time, we believe this is a reasonable way to think about the recovery when modeling 2022. In closing, we made good progress in the third quarter and remain on track to drive growth and scale profitably in our core business in the years ahead. We are in a great position strategically with best-in-class SCS technologies, remaining share gain opportunity, future growth opportunities in PDN and NSRBP, superior clinical data, and a strong commercial organization. We continue to advance our operating margin expansion efforts with many of the changes we're investing in this year, such as our integration of manufacturing in Costa Rica, development of the PDN market, and the Omnia upgrades that facilitate greater commercial productivity, all expected to provide continued improvement in our financial leverage as we grow. That concludes our prepared remarks. I'll turn the call back over to Julie to moderate the Q&A session. Thanks, Rod. In order to get through the question queue efficiently, we ask that you please limit yourself to one question and one quick follow-up. You can then rejoin the queue, and if time allows, we will take additional questions. Operator, we're ready for the Q&A instructions. At this time, I would like to remind everyone in order to ask a question, press star, then the number one on your telephone keypad. We'll pause for just a moment to compile the Q&A roster. Your first question comes from the line of Joanne Wuensch from Citi. Your line is now open. Good afternoon, thank you for taking the question. You'll be surprised it has to do with PDN. It's really a two-part question. One is, what is the most positive thing and negative thing that you have learned, post the launch? The important piece of this is when you describe ramping quote gradually over time, can you give us a little bit more color over or about that and how you think about the consensus estimates for PDN next year? Thank you. Thanks, Joanne. You know, there really hasn't been much we've learned that's negative. I would say that certainly we have been validated in those things that we thought would be challenging. I think maybe top on the short list would be conversations with our PDN patients are a little bit different than conversations with our normal lower back and leg pain patients. On one hand, they're extremely eager and receptive for anything that might be helpful. On the other hand, they're typically just not used to talking about interventional alternatives or surgical alternatives. I think it is sometimes with some patients a longer conversation that has to take place for them to begin to get comfortable with something other than drug alternatives. I would say that's sort of in the margin, and it, most of this has been extremely positive. I would say you know, maybe the most positive, again, is validation, I think, of what we anticipated. In other words, I don't think there have been a lot of surprises. The extent to which our existing customers are eager to develop their own local markets, to reach out to their own referral base, to look at their own electronic health record information to find patients, all of that has been really gratifying. In some cases, a little bit surprising, the extent to which our customers wanna go to really identify and help these patients, and of course, to generate a steady referral stream to their practice. In terms of the PDN ramp throughout next year, our point is only just to remind people that it does take some time to generate a brand new stream of referral patients in a new indication. Once patients begin to fill that funnel, they have to go through the process of getting in to see the pain doctor, of getting insurance approval, getting their trial, getting the perm, et cetera. Joanne, it wasn't meant to convey any change in our expectations for 2022. We're actually very excited about the impact of PDN on this business next year, and we'll speak more about that, presumably when we talk about 2022 in the first quarter. Thank you. Your next question comes from the line of Chris Pasquale from Guggenheim. Your line is now open. Thanks. Keith, I wanna understand better how you're thinking about the fourth quarter, because there seems to be a bit of a disconnect between the comment that you're seeing improvements, that continued into October. Then the guidance which, you know, based on my math, looks like it implies U.S. sales that are down about twice as much ex PDN as what we saw in the third quarter when we compare it against the 2019 baseline. Can you just clarify the assumptions there and how you landed where you did for the fourth quarter? Yeah. I'll let Rod weigh in on this as well. I mean, I'll tell you that you know, when we're almost at the halfway point through a quarter and we're talking about that quarter, the expectation for that quarter becomes reasonably mechanical. You know, we have a model that looks at the number of patients who have been trialed, and we know what portion of those patients move to perm and what the revenue impact will be. So it's fairly straightforward. I will add two other things. One, you're talking about a comparable of 2019, and I'll remind you that the momentum building in this business in 2019 in the fourth quarter with the Omnia launch was pretty significant. That may be, in some ways, a function of a comparable period as much as anything. Too, I know that we've seen a little bit of a flattening of the trial-to-perm conversion curve, and it's nothing more than the friction in the system of getting patients scheduled, with, in some cases at least, restraints on capacity, labor shortages, et cetera. We've seen just a little bit of an extension of that timeline from when patients get their trial to when they get their perm over month one, month two, month three. That certainly impacts our model as we think about Q4. Otherwise it's pretty much that straightforward. Rod, do you wanna add anything to that? Yeah, sure. Chris, I mean, Keith hit the big points. Just to reiterate a couple of them and to maybe provide a little more color. The jump in 2019 from Q3 to Q4 was unusually large, and that goes to Keith's point about Q4 being a particularly strong quarter for us with the launch of Omnia back then. Secondly, what I'd also point out is while we've continued to see some improvement on the trials and perms throughout Q3, we are still seeing some COVID headwinds that impacted us to a net negative in Q3, and we're still seeing some of those headwinds as we're, you know, through one month of Q4 already. That is certainly tempering some of the results in Q4 here. Thanks. That's helpful. Maybe just to follow up on that, can you give us any sense of the magnitude of improvement you've seen from maybe whatever the trough point was during the third quarter to where you were in October? I don't know what the right benchmark is to sort of weigh that against whether it's July or some other period, but just a sense of magnitude of improvement that you've seen would be helpful. Thank you. Yeah, I think you know if you think about activity, it's probably best to look at trial volumes and at least in the U.S., I think from trough to October, you know, you're probably looking at you know something in the range of 15% or so in average daily trial volumes ending in October. Also remember July was particularly impacted by vacations this year as well. Okay. Thank you. Mm-hmm. Your next question comes from the line of Tom Hopkins from Bank of America. Your line is now open. Oh, thank you. It's, can you hear me okay? We can, Bob. Oh, great. Thanks, Keith. So, you mentioned 2022 a few times on the call and you clearly sounded confident, but then you suggested you may not guide for the full year. You know, interestingly, you talked about what you're hearing from doctors in terms of the pace of the recovery over the next 12 months. You're sort of giving us, I guess, the range of what you're hearing out there. I know you're not giving us guidance on this call, but you mentioned 2022 a few times, and you talked about what you're hearing from doctors. I was just wondering, like, what does that all mean? You know, how do we interpret those comments from you guys, at least directionally? I was wondering if you could just give a little more help there. I mean, does it mean similar growth off of a lower base? Just wondering if you could elaborate on those comments. Well, let me say a couple of things. First of all, to Chris's last question, Bob, before you cued up, I think that trough to peak is actually more like 20% in daily trial volumes, and not 15%. On the 2022, we're just trying to be constructive, Bob. I don't think it's really anything more than that. It's a really dynamic environment. We know we don't have guidance in place for 2022. We're at this point unsure of whether that guidance when it comes will be for the first quarter or for the first year, depending on the visibility we think we have. We're looking at just the trends, day-to-day, week-to-week, month-to-month, in terms of customer activity, patient visits, trial volumes, and a number of other things. Absent another peak of some sort in a COVID-related issue, like infection rates or something else, it does feel like things are beginning an upward trajectory in this particular therapeutic category. Now, you and I both know that could change as facts change in the next 90 days. We're stopping short of giving a lot of specifics about 2022. By the way, we wouldn't be doing that at this point yet anyway. We're just trying to be as constructive as we can with the amount that we know and don't know today as people think forward. Maybe just elaborate on your comments on what you're hearing from physicians in terms of what they think of the pace of recovery. You know, it's interesting commentary. I'm just wondering if you could kinda elaborate and help us understand, you know, why you presented us with that those data points. I think it probably shapes the way we think about what the next you know 14 months or so are going to look like. Again, absent some new facts, some new change in this particular part of our environment. You know, I think that we view this as being probably a steady rate of improvement for the most part, between now and the end of 2022. As you think about historic growth rates in this business, we can continue to feel a little bit of a pinch here in the next 60 days, though getting better as it has in the last 60 days, and getting to a point sometime in 2022 where you're sort of at water level. Really kicking into traditional and then maybe even growth rates that are above historic growth rates sometime after that. All of that is, you know, a lot of color and no numbers, Bob, and I realize that. We're not giving guidance for 2022 today. Other than to say, we just think that performance over the baseline will continue to get better between now and the end of next year, provided there's not another change in this part of our environment. Okay, great. Thank you very much. Your next question comes from the line of Robbie Marcus from JP Morgan. Your line is now open. Hey, guys, this is Alan on for Robbie. I hate to follow up on it again, but I guess another way of, you know, maybe diving a little bit deeper into your fourth quarter is, you know, this quarter you provided a pretty detailed breakdown of, you know, the canceled patient impact of 3Q 2020 versus this year. Do you have that for 4Q 2020? And is that kind of a dynamic that's influencing what that sequential growth rate looks like? Yeah. Hey, Alan, this is Rod. We don't have that breakdown for the fourth quarter, largely because it hasn't occurred yet. We do anticipate and continue to see some pressure in certain geographic areas in the U.S. and internationally on canceled cases, both from a patient and from a capacity or staffing shortage perspective. We monitor that super closely. You know, we're starting to see some encouraging news out there, but we do continue to see some headwinds as we go into Q4 here. Oh, sorry, just to clarify, I meant like the 4Q 2020, right? 'Cause you had the net impact for 3Q 2020 as well. Oh, got it. Okay, for Q4 2020. Sorry about that. Yeah. The net impact on Q4, if you remember last year, we had a resurgence in COVID starting in November and December, and we had in the neighborhood of $5 million in canceled cases in the fourth quarter. I think we spoke about that in our Q4 earnings call last year. Offsetting that, we also had the recovery of backlogged cases in the neighborhood of, you know, high $3s to $4 million. Net-net, it was about a -$1 million impact for Q4 of 2020 last year. Got it. Just quick follow-up on PDN. You know, it's relative to our expectations, at least it seems like that third quarter, you know, definitely went very well for you. When we think about fourth quarter and really driving that momentum continuing to 2022, how should we feel about, you know, your strategy developing? I know you continue talking about investing into, you know, leveraging additional clinical data and maybe some DTC as well as growing DTC from your customers. Any color on that would be great. Thanks. Yeah. I think we're looking at all those things. In fact, our DTC investment has risen pretty steadily over the course of the year, and certainly over the last few months with regard to PDN. We're also looking at other things. Some of the levers we've been pulling up in the initial portion of our launch to try and establish results, returns, and decide how we wanna handle some of those things into 2022. I would say we're looking probably most heavily at our direct referral selling organization, which seems to be generating a lot of activity and high-quality activity in terms of patients that convert to trials and to perm. I think trying to understand how and at what pace we expand that is probably high on our list right now. Your next question comes from the line of Cecilia Furlong from Morgan Stanley. Your line is now open. Thanks for taking the question. This is Calvin on for Cecilia Furlong. Two questions from me. The first one is just on, can you touch on the outlook around the core SCS market recovery versus the outlook for the PDN ramp? You know, both are deferable procedures, and PDN is clearly more of a market development story today in terms of driving growth. But are there any specific dynamics on recovery between the two that are worth noting coming out of the peak of the Delta variant? Just considering you broke down your Q3 and Q4 numbers broadly versus your general full-year 2021 guidance. But you know, your PDN number of mid-single-digit $ million hasn't changed. Perhaps it's just a larger range. Could you comment on any difference between kind of the two recovery paths? Well, we don't have much to compare the PDN numbers to. The market is so nascent in its development that we're talking about small numbers. I don't doubt for a moment that PDN activity is impacted every bit as much as lower back and leg pain patients. It's just that we don't have comparable numbers. We don't have prior year, prior quarter, et cetera, to compare to. They're still relatively small numbers. I would say maybe more qualitatively, I don't know that I see a dramatic difference. In other words, in terms of the flow of patients, if I think about the COVID impact on patient reluctance, on center capacity, on labor issues, etc., I don't really think there would be a meaningful difference in the impact on one segment versus the other. It's just that it's much easier to quantify in the lower back and leg market for SCS because that's the established portion of our business. Understood. Just on backlog, as you think about backlog, either from a trialing or from an implant perspective, how are you setting your goals in terms of how much backlog you wanna clear by the end of 2021? Perhaps, you know, what percent is expected to spill over into 2022? Thanks so much. Yeah. Hey, Calvin, this is Rod. You know, we've actually done a really good job of clearing backlog in the business, and we've continued to stay really close to the customers or the patients. I would not be expecting a large amount of that to be going into 2022 as we continue to, you know, bring these patients, you know, back into therapy. Great. Thank you. Your next question comes from the line of Matt Taylor from UBS. Your line is now open. Hi, thank you for taking the question. I did wanna follow up on some of the PDN commentary that you made. Can you help us, I guess, bridge between you talked about in Q3 doing, I think it was 175 trials and, you know, seeing some pickup in Q4. Having generated, I think 20,000 leads overall? Just hoping that you could talk about the process of bringing those 20,000 through the funnel and the steps in the process, any, you know, timing on that? Help us think about the shape of the ramp of those qualified leads through 2022, if you could? Yeah. It's a great question, Matt, and I say that because I'm not sure we actually have the answer to that yet. It's just too early. If you look at the trials that we've had thus far, many of them of course have come from our new initiatives and our new efforts to develop those leads and referrals, either directly with the patient or with the referring doctor. Frankly, some of them came from an existing pool of patients that were being watched by our existing customers. We know that we've generated a ton of interest. We've got a lot of leads. We know that we're beginning to turn those leads into referred patients. Trying to quantify how many of those leads become referrals, become trials and perms is just a little bit too early to tell. I don't think if I look at our the impact on our business in Q3, I would say we've not yet really begun to see a big part of the advantage of the direct efforts with, particularly with patients. One of the things we know about direct-to-consumer initiatives in our core market is that when we identify a lead, on average, for those who turn into a trial, it takes about four months for that conversion process. Now that's not the trial to perm timeline, that's lead to trial. We know this process, when you're dealing directly with patients, takes some time, even with the qualified leads who go on to trials. I would say give us another, probably another quarter or so before we can begin to kind of quantify the shape of this funnel. All right, great. Thanks, Keith. Mm-hmm. Your next question comes from the line of Danielle Antalffy from SVB Leerink. Your line is now open. Hey, good afternoon, everyone. Thanks so much for taking the question and giving all the color. Keith, you made a comment that piqued my interest, and that was around you know, getting into competitive accounts with PDN. I'm curious if you could elaborate a little bit around that sort of, you know, I appreciate there's this COVID impact, and so it's probably tough to say how to think about it consistently going forward. But just sort of what you're seeing from a halo effect, perhaps, where you're getting into new accounts with PDN and their adoption of the technology for their sort of bread and butter back pain patients. I had one quick follow-up. Sure. Thanks, Danielle. I'll give you kind of the color around it. That is really sort of, I think, what you might suspect kind of the obvious, and that is that there are a lot of pain doctors out there that deploy SCS therapy with whom we don't have a day-to-day, quarter-to-quarter business relationship for a variety of reasons. That's true for all the participants in this space. All of these doctors, virtually all of them, I would say, have an interest in treating PDN patients. They understand it. It makes sense to them. They believe the data, and it's hard not to. They wanna participate. They wanna help these patients, number one, and they wanna participate in the growth of this new application of SCS. To do that, to do it on label, to do it with a technology that's invested in generating data where they kind of understand what the outcomes are going to be, to be able to get these patients through their payers, all of those things requires a partnership with Nevro. We assumed this would be the case, and we haven't been disappointed. It doesn't mean that when a doctor decides to use Nevro for PDN, that he's gonna replace all of our competitors' volume in that account. It does mean it allows us to begin to build relationships with customers with whom we didn't have relationships in the past. That will undoubtedly because of the advantages of our therapy, we believe, mean that we begin to capture some of their core business in those markets. That certainly would be our hope and what we would strive to do. That's what we would have thought going into this. In fact, I think in the early days, that's what we've begun to see. Okay, that's great color. Then my follow-up is around getting these patients back into the funnel. I'm just curious if you could talk about some of the areas. Is it that the patients are being, you know, managed medically and thus sort of get lost to the system? Or should we be thinking about this as some of these patients are kind of lost forever? Maybe a little bit more color on why. You know, you think logically this is a disease state where, you know, it's not necessarily life or death, so maybe there's some hesitancy for them to ever come back into the system. Can you talk a little bit about that? Maybe give a little more color around what you're seeing there. [crosstalk] Thanks. I can. I mean, we've done a fair amount of research with patients and their pain doctors on this point. I'll tell you what I think we said last quarter, which is when we talk to these patients, 90% of them say that their pain has not gotten better during this time. Half of those patients say their pain has gotten worse. Now that leaves 10%, obviously, that either said it's gotten better or gone away or they've sought other treatment, et cetera. It's a small number, but it's not completely insignificant. For the most part, patients say that they're not doing better. They may be doing worse in many cases, and they still intend to seek care. That tells us that the demand that would have been there among these patients who haven't sought care will still be there. Now, that doesn't mean all of them will show up for therapy. I don't think, frankly, we don't understand of that pent-up demand, what portion will come back and over what time they'll come back. I think it's unreasonable, I think, and flies in the face of all the work we've done to assume that all of those patients who haven't sought care over the last 18 months just won't and somehow have found relief some other way and aren't going to seek care. We also know that of the patients we talk to on a regular basis, we will ask them how many visits they've made to a pain physician in the trailing 12 months. That number continues to go up. The reaction to our online engagement with patients on lower back and leg pain, search results, et cetera, those numbers continue to go up. We're starting to see procedures that typically precede SCS like injections and radiofrequency ablations begin to tick up a little bit. That's not a direct tie it's that we can quantify, but it is indirectly an indicator. I think we're seeing some signs that many of these patients still intend to seek care. Danielle, I couldn't begin to tell you if it's 30% or 90%, if it's over six months or two and half years. We do think that many of those patients intend to and will come back to therapy. Okay. No, that's helpful. I appreciate it. Thank you. Thanks, Danielle. Your next question comes from the line of Margaret Kaczor from William Blair. Your line is now open. Hey, guys. This is Maggie Boeye on for Margaret Kaczor today. I wanted to ask on PDN a bit more. With your sales reps for core back and leg assisting with the PDN launch, how is coverage managed to ensure that you're still reaching your traditional pain docs who may not focus on PDN patients? And then what does this mean for 2022 sales rep coverage? Do you have plans to hire additional reps to cover? Thanks. It's really not an either/or. We're not asking our traditional sales force to say, "Okay, continue to build your core business 80% of your time and focus on PDN the other 20, or focus on PDN doctors 20% and then go see your other customers 80%." These are all the same pain docs. The number of pain doctors who deploy SCS as a therapy in their practice who don't intend to treat or don't see or don't want to see PDN patients is virtually zero. I don't really think we're asking our existing reps to make a trade-off of one part of the business for the other. Their job is, I think, to help our clinicians who really wanna build this part of the practice, who wanna reach out to their local community, make sure that they have the tools that we can provide to do that, and to make sure they're partnering with their local PDN referral rep. We haven't from the beginning, and I still don't see this as a trade-off where we're taking our hands off the wheel on one part of the market so that we can steer the other part. In terms of the number of core reps, you know, we continue to find a lot of efficiency there. Our territory structure is still, I think, less than it was in early 2019. I still think we have a fair amount of capacity. How have we done that? We've done it by putting more therapy consultants in the field to work with their patients, by putting more HFX coaches on the phone to work with their patients, and of course, by using these new PDN reps to generate referrals among referring doctors so that they don't have to do that. Essentially, we've made a smaller number of sales reps more effective. I think, and by the way, some of our product changes play into that as well that we've introduced over the course of this last year. I think that's a trend that will continue. I don't think as you look at 2022, maybe even a good portion of 2023, that our quota-carrying footprint really needs to change much. Got it. Thank you. Just one more follow-up on PDN. I just kinda wanted to ask about the progression of investing you plan on doing for market development as you head into 2022. Thanks. Yeah. I think we'll probably quantify that a bit more when we talk about 2022 in the first quarter. I wouldn't expect an enormous step up. We front-loaded that investment in 2021, particularly in the back half of 2021. There'll be some full-year calendarization impact of the investments we made in the second half carrying into a full 12 months in 2022. There will be some step up in investment, but I wouldn't think of this like a doubling or tripling of investment to develop this market. Got it. Thanks so much. Okay. Your next question comes from the line of David Rescott from Truist Securities. Your line is now open. Hi, guys. Thanks for taking the question here. I guess sticking first with PDN, I mean, I think you had mentioned maybe around 6% of trial volume was from PDN in Q3, and maybe around half of those or so converted to a permanent implant. I guess the first question is why, I guess, is that, you know, somewhat lower than where we see kind of traditional trial to permanent implants for core SCS? I mean, is it patient selection? Is it kinda the efficacy? Is it patient hesitation? I mean, is there any difference between why there's a different rate between PDN patients and, I guess, this core SCS business? Then, you know, around 6% of trial volumes today, I mean, if we think about that increasing into 2022 or maybe having an increase in the conversion to permanent implants, I mean, could you see PDN being, you know, say anywhere from from 10%+ of the business in 2022? Well, let me answer them in order. They're not converting at a lesser rate necessarily. The difference is just timing. The difference is, you know, it takes time for trial patients to convert to permanent implants. It's a reasonably predictable curve that starts in the first 30 days, picks up dramatically in the second, third, and part of the fourth month, and then has a long sloping tail where you have patients who have a trial that convert to their permanent, you know, six or seven months later. There's a conversion curve for those patients who have successful trials. The only difference in this, you know, this 70-something over 170-something is just that we're only 60 days into this or 90 days into the launch, and really probably 60 days past most of these trials at the latest. I don't think we expect a difference in that regard. The difference here is just timing. In terms of the percentages of the business that PDN could represent, look, let us give us a little bit of time to get some more data under our belt, and we'll talk about that when we talk more about 2022 next quarter. You know, we've talked about this in the past. Could the PDN market be 10% of the traditional lower back and leg pain market, over time? Absolutely. It could be much more than that over time. Where it ends up at the end of 2022 is another issue. If you give us a little time to get our arms around some of those things, we'll talk about it more in the next quarter or two. Okay. Thanks for taking the questions. Again, if you would like to ask a question, press star then the number one on your telephone keypad. Your next question comes from the line of Suraj Kalia from Oppenheimer. Your line is now open. Keith, can you hear me all right? Yes, we can hear you. Perfect. Hey, Keith. The PDN DTC referrals that you mentioned, I believe I heard the number 500 to SCS docs. How does the HFX team and your PDN specialists interact with the endocrinologists in this referral chain? Well, through a variety of ways. Suraj, you might remember that the primary targeting mechanism was prescribing records for these patients. Some of the referring doctors are endocrinologists, some are primary care physicians, some are podiatrists. I don't know that our interaction with the endo universe has been meaningfully different than the rest of them. We interact with them through our referral sales organization. We interact with them at clinical meetings through presentation of data, through virtual education events and increasingly now some physical education events. Some that are put on by the company, some are put on by local pain physicians. There's a number of ways that we're reaching the referring doctor, whether it's endocrinologist or not. That was, you know, consistent with the launch plan that we talked about a couple quarters ago. Keith, my follow-up, the third you mentioned about your PDN physician survey, how was that distributed US versus OUS? Any additional color would be great. Thanks for taking my question. I believe that market research was all domestic. So when we talk about, you know, what pain physicians were saying about their expectations for pace of recovery, Suraj, I'm 90%+ sure that that was a U.S. market research initiative. I would expect, by the way, if we had included other markets in that market research, I would expect it based on what we do know to be roughly similar. It might be slightly more pessimistic about the pace of recovery. I think that's not unusual to see that in market research like that, but I think it would be largely the same. Okay, your next question comes from the line of Bill Plovanic from Canaccord Genuity. Your line is now open. Hi, it's John on for Bill tonight. Thanks for taking our questions. I appreciate the commentary on your patient survey. Have you thought about or created any education or initiatives on alleviating the financial fears for patients? What do you think helps solve the dynamic? I'm sorry, I didn't understand the question. Could you please repeat the question? Sure, yeah. Have you thought about or created any education or initiatives on alleviating the financial fears for patients that you mentioned in your patient survey work? Yeah. We're continuing to explore options on how to bring patients, more patients into the funnel. We're approaching it from a number of different angles. I'd say hold tight on that as I think we'll have more information coming, you know, within the next couple of months. Great. Thanks. On PDN, what's the pre-authorization success rate that you've seen so far? Yeah, I think it depends on the payer. It's been. There really haven't been any surprises there. You know, I think we expected to have a pretty high success rate in parts of the country where Medicare is paying, and in fact, we've seen that. I think we probably, if there's been a surprise there, it's been the mix of the patients. While the numbers are still very low, the mix of the patients looks so far sort of similar to our base business, which is, you know, roughly speaking about half Medicare and half commercial payers. That's been a little bit of a surprise to us. We have been fairly successful adjudicating patients prior auth, even prior auth denials on the second round for PDN with commercial payers. And that's done locally. That's not a centralized coverage policy, of course. We thought we would have some success there. I think the numbers are probably still too small to reach any sweeping conclusions, but we've been kind of pleased that that's been effective so far. Great. Thank you. Okay. There are no further questions at this time. I would now like to turn the conference back to Mr. Grossman for closing remarks. Okay, thanks, operator. Thanks everyone for joining us today. Thank you for your questions. We appreciate your time today, and we'll look forward to updating you further in the following quarter. This concludes today's conference call. You may now disconnect.