Hi, welcome to the session on the role of peripheral nerve simulation in physiatry practice. It's a real privilege to moderate this session, and I'm joined by a great faculty, including Dr. Garan from Ohio and Dr. Spinner from New York City. And this is an area that's really exciting to discuss, and I'm really looking forward to hearing from both of our speakers, because there's been so much development in peripheral nerve stimulation over the last several years, and it's really come to the forefront as a therapy that has become much more of an option in the treatment of our patients. In my opinion, it's allowed us to treat patients that we otherwise were not able to in the past and provide options that are cutting edge and minimally invasive while also sparing medications, which is obviously a big push in the country right now. So with that, I'm going to get right into it. Again, I'm Mehul Desai, I'm from Washington, DC, the epicenter of all sorts of exciting events these days. And if you see me moving my computer around, it's because I'm having trouble getting my face into the screen properly. I'm in private practice and was previously in academic medicine for about six years at George Washington University and started my own practice in 2016. With that, my disclosure slides, I do have some relevant disclosures, but none of which I'll be specifically discussing during today's discussion. So jumping right into it, the history of peripheral nerve stimulation. So for those of us who've been around for a little bit of time and perform peripheral nerve stimulation for several years now, we know that there's been an enormous evolution in the technology and the approaches. So if you go back in history a little bit here, and frankly, probably at a time when none of the panelists were even quite born yet, including myself, what you have is in 1967, you have the use of infra-orbital electrode placement, just sort of used to demonstrate the proof of concept and the proof of the principle. Then you have the first reported case of an implanted PNS for complex regional pain syndrome in 1970. And so we went from a time when we were using this therapy via an open technique where the neurosurgeon or a similar surgeon of that kind was exposing the nerve, visualizing the nerve, and then placing electrode directly on the nerve. That sort of evolved in 1968 with the first FDA cleared neuromodulation system specifically for PNS. And then in 1996, there were some publications that demonstrated long-term relief with the use of peripheral nerve stimulation and lead placements. Then we're continuing to have evolution in the therapies. And one of the things I'll talk a little bit about in the next several slides is you had miniaturization and improvement in technology, but really we didn't get that vast improvement until the last five to 10 years when you really got therapies that were specific to peripheral nerve stimulation. Prior to that, a lot of us were doing therapies where we were adapting spinal cord stimulation leads or whether they're percutaneously placed or open placement based to place them along nerves to get coverage or to stimulate peripheral nerves. Similarly, there was a time in the early 2000s where we were really doing a lot with peripheral nerve stimulation, sort of a little bit of a black hole of stimulation where we place leads subcutaneously with the hopes of getting low back pain coverage. And there was enough anecdotal evidence there that people got really excited about it, but it very quickly sort of died away as well. In the last four to five years, we've had an RCT looking at the significance of permanent peripheral nerve placement versus sham that was published by Dr. Deere in 2016. And then we've had Dr. Gilmour do a lot of exciting work from 2018 into 19 and 20, looking at patients with post amputation pain and also low back stimulation along the medial branches to get coverage of low back pain as well. And a lot of that current work was sort of pushed to the forefront by work that was done previously. And, you know, as with most things we build on the shoulders of those who came before us. And there was a lot of interesting work done in post stroke shoulder pain, which is obviously a disease state that's near and dear to the hearts of physiatrists everywhere. And we see this all the time in our practices. So back in sort of what was PNS like a few years ago and where is it moving towards? So typically it was a neurosurgical exposure and a neurosurgical procedure. Contact positioning was critical. You had to be right on top of the nerve. We were looking at nerve injury and fibrosis related issues because when you expose the nerve and tried to place a lead along the nerve, the risk of injury or scar tissue formation was a lot higher. We were focusing, as a result of this, the focus was really on spinal cord stimulation rather than peripheral nerve stimulation. This procedure was more permanent and more invasive and really focused on primarily neuropathic pain and often used as a salvage therapy. It was a last resort. It was a treatment that we used when everything else had failed. Fast forward to 2020, now with the advent and as the two speakers who are on the call today or on the conference call today can attest to, especially with their ultrasound knowledge, I mean, ultrasound has really transformed this space. And I think both the folks who are going to be talking have such great ultrasound skills. I'm personally really excited to hear what they're going to talk about. It's also now a percutaneous intervention, much easier to place, much less invasive. You're able to get the lead close, but doesn't necessarily always have to be right on top of the nerve, which allows you to remain somewhat remote to the nerve, thereby reducing your risk of nerve injury and fibrosis, easier to use, easier to replicate, really low infection risks for the most part if you use good surgical technique. There's durable relief in some cases, even if you have a lead or a device that's not permanent and therefore you've got these treatment options that are both permanent or temporary that both seem to offer really great options and you're able to pick the right therapy for your patient as opposed to have only one option. And we've really expanded the applications even beyond neuropathic pain. So now we're looking at some nociceptive conditions that are obviously always neuropathically mediated but we're able to interrupt the pathway by blocking or treating the nerves that innervate certain nociceptive structures. And as a result of that, not only have various disease states that were historically unamenable to treatment become now accessible to treatment, but also the positioning of this therapy earlier on the continuum has gained popularity and favor. Why not treat a patient early? Why wait till six months, 12 months, two years? Why not help the patient not transition into a chronic state and maybe help them in a more subacute state where you're able to intervene and to change the disease course so that the patient is much improved. So we've had some longstanding beliefs that pain relief without paresthesia was impossible but that it turns out that lots of work has been done about a paresthesia-free stimulation. And a lot of the new manufacturers that have peripheral nerve stimulation devices have very, quite a variety of options with programming, which is great because you're able to use different modalities for different patients as their needs might be different. We're able to place leads anatomically as opposed to just physiologically, which is beneficial. You may be able to use lower amplitudes, so not getting some of the side effects that can come from having higher amplitude settings, realizing that you don't need a positive response to nerve block. This is not always predictive of peripheral nerve stimulation outcomes. We also realized that we can be close to the nerve depending on the configuration and the geometry of the stimulation parameters achievable by the specific device so that you don't have to be right on top of the nerves. Also seeing that even just motor activation can result in sustained pain relief and realizing that there's lots of different options. You can have a permanent placed electrode and device, you can have a temporary place device, and some of these, some of both of these can provide longstanding and possibly in some cases, permanent relief. So where does peripheral nerve stimulation really fit? I don't think I have an absolute answer to that. In my practice, it's certainly moved up quite a bit in the algorithm, and I think for those folks who will tune into this talk, I'll be excited to see what they think and what they see with Dr. Garan and Dr. Spinner's presentations, because I think both these folks have really shown how this therapy can be moved up into the treatment continuum and how it may provide benefit to patients who otherwise would have to wait longer or have more invasive procedures. In just a quick example, in my practice, I've begun to, specifically for my younger patients, really de-emphasize medial branch radiofrequency ablation in the lumbar spine, because I think that, I believe that if we're able to provide an option that's motor sparing and nerve sparing, as opposed to ablating the nerve, we might be doing, doing some of these patients a large service rather than denervating a young person's medial branch, medial branches. So just one example, maybe how this therapy is changing and how it's being repositioned in different practices. So how does it really work? Well, sort of like spinal cord stimulation, we're not 100% sure. We have a lot of theories. Many of them are somewhat antiquated in the sense that we've always sort of clung on to this theory that the proposed mechanism of action was that pain relief was achieved via primary activation of sensory afferents. It's essentially the classic gait control theory that we've always sort of talked about when it comes to spinal cord stimulation, where the body can only theoretically respond to one stimulus at a time and therefore ignores the more painful stimulation by activating sensory afferents. So some of that is changing. We're really digging into this a little bit and realizing that, you know, this is just a slide that talks about how noxious stimulation of the sterile nerve evokes a pain signal transmission, whereas peripheral nerve stimulation may inhibit pain signal transmission. So maybe it's not as simple as just the gait control theory. So some of the things that have been proposed at this point is that pain relief may actually be achieved in these patients via indirect activation of sensory afferents following efferent activation. So by getting efferent activation, you're getting the sensory feedback loop where patients are having less pain. And so I think it's, you know, certainly there's more work to be done, but these theories are being expanded to include things that we maybe historically haven't thought of as much. Some of the sort of nuances, what you get here is indirect activation of afferents via peripheral nerve stimulation induced motor activity. And this is usually via the muscle spindle and the Golgi tendon organ, which the muscle spindle is a length indicator. The Golgi tendon organ is a tension indicator, and you get convergence of tactile and proprioceptive afferent input with overlapping large diameter fiber morphologies, dorsal horn projections and spinal thalamic pathways and convergent activation of inhibitory networks in the dorsal horn. So these theories are evolving. We're sort of learning more and more as we go on and learning that maybe the sort of historic constructs that we've had with regards to achieving pain relief with neuromodulation of any sort, it may be, A, dependent on what kind of modality you use, but also likely much more complicated than something as simple as the gait control theory. So what do we know about the pain cycle? So we know that oftentimes with chronic pain, pain lasts long after the noxious injury that occurs. There's decreased activity and movement as well as guarding that results in maladaptive behaviors. This then signals neural signaling changes with increases in abnormal and spontaneous afferent signaling, which then results in central sensitization and ultimately maladaptive cortical plasticity. So how does peripheral nerve stimulation interrupt some of these pathways? And so it reduces this by reducing pain after musculoskeletal injury, encourages healthy behaviors and increased levels of general activity. There's increased healthy afferent spontaneous signaling, which decreases abnormal signaling, which then modulates and modifies central sensitization and reduces hypersensitivity to normal inputs, thereby potentially reversing maladaptive cortical plasticity. And it rebalances the neurologic system. So with that, transitioning into what's really driven some of these changes, two big things have frankly driven some of these changes, innovation and reimbursement. So I think there's been a change in work our views as it relates to peripheral nerve stimulation, which has helped with at least the kinds of work that we do and the kinds of energy we put into these treatments. But really, we've had a lot more access to therapies via innovation than we once did. So we've got manufacturers working on miniaturization, external power sources, and changing programming parameters. We've got various electrode configurations that are much more suitable to these treatment options and to being optimized for these kinds of disease states. So without naming a lot of names, there's a whole host of manufacturers that have slightly different platforms, for lack of a better word. What we have here is a device that's got a monopolar coil electrode, and it's got a built in anchoring system and a deployment system that allows it to be placed easily. It's got a handheld controller, as one can see on the right side of the screen. So this is a monopolar device with an external battery that's got essentially a receiver at the one end of the electrode or of the lead. Here's a device that's a little bit more conventional in the sense of what people are accustomed to seeing, at least with regards to leads, where you've got different configurations of electrodes and contacts. But again, you've got a receiver that's internalized, but the entire generator system and battery, quote unquote battery, is all external. So more conventional looking as far as the leads are concerned, but in terms of driving energy and generating power, all of it's externalized. Here's a manufacturer that is similar. It's got another external device that is basically this therapy disc that can be placed on the skin to be able to drive current across to the leads and across to this small IPG that's internalized, along with the electrodes, again, that look more conventional in design. And finally, you've got a device that's actually temporary. That's a device that's placed via a needle with a monopolar distal contact and a very specific geometric configuration and design so that there's some tissue ingrowth so that there's engages and encourages stability of the device, but also this is an external battery unit. And that's sort of the consistent theme in the new devices, that all of them have externalized power. And it really does allow for therapy flexibility and the ability to really optimize treatment as needed. So with that, I'm going to turn it over to Dr. Grand for her section. And looking forward to hearing what she has to say. All right. So yes, I'm Dr. Catherine Grand, and we're going to move on to the part where we fit this into the physiatry practice. So disclosure, I am a consultant for SPR Therapeutics, but I will not be talking about anything specific at this time related to that. So our goals for this session is to understand how physiatry is uniquely suited for peripheral nerve stimulation and how that might fit into your practice. So I essentially took this directly from the AAPMNR website. Dr. Desai did a great job of covering the peripheral nerve stimulator component of our discussion. So this is a general sense of who we are and what we do. I like to personally focus on the part about comprehensive patient-centered treatment plans in order to maximize function and quality of life. And I'll come back to that a couple of times throughout this presentation. And this slide, again, taken directly from the website, is a list of different things that we treat. Clearly, I could not fit everything onto this one slide. We treat a whole lot of things, but just a sampling of those. And then I put circles around the many areas that can be treated with peripheral nerve stimulation, and especially with some of the newer and ongoing research areas. Clearly, I'm not discussing all of these spots, though. And I do like to point out, too, that ultrasound training has become a more important part of our training as physiatrists, but also a very important role in peripheral nerve stimulation. And so right now, it's being taught in residency, taught and beyond. And this conference, too, has opportunities to learn more about ultrasound and how to incorporate it into your practice, which I know Dr. Spinner is probably going to enhance on that as well. So our role is, how does it fit together? So I put in a couple of cases on how peripheral nerve stimulation may fit into your practice and things that you've already go through. So our first case, a 36-year-old male, traumatic bologna amputation. He's seen in the clinic because he has pain and can't tolerate his prosthetic anymore. He has no wounds. Everything looks intact and well-healed. So you go through your typical history physical. Otherwise, healthy male, has residual and phantom limb pain. He has a very well-healed residual limb, no contractures. He's been doing everything he's supposed to with physical therapy. He was discharged by them. They didn't have any further recommendations. He's been wearing a shrinker socks, doing his exercises. He just can't tolerate his prosthetic. He has no wounds. He has no contractures. He just can't tolerate his prosthetic. He has so much pain. We do some imaging. Everything looks normal. And I think it's really interesting that the study done in 2005 found that up to 95% of amputees report some degree of pain, with at least 50% to 85% of those experiencing phantom limb pain. So you go through your typical treatment plan and where my peripheral nerve stimulation fit in here. Does it fit in for those who are just not responding to treatments or maybe who those are not appropriate for your typical progression? Maybe at this spot. This next, this first study was done in 2018, published in Regional Anesthesia and Pain Journal in January of this year. And it was a randomized, double-blind, multi-centered study. It was, had a patient sample included lower extremity amputees due to trauma with residual or phantom limb pain, who were using a wide range of opioid or non-opioid drugs. Using a wide range of opioid or non-opioid medications prior to the study, as well as going through physical therapy. They were divided into two groups. Group one had a peripheral nerve stimulator placed to the femoral and sciatic nerve of the amputated leg for 60 days. And then group two got a sham stimulation placed and then was changed to treatment at four weeks. All leads were then removed at the end of the treatment time. Results showed a significant difference in pain reduction even at 12 months in group one and also notice decreased depression, improved sleep, improved walking, and quality of life in the treatment group, which is very important. So the color graph above I like as well it shows at baseline at the end of the 60-day treatment as well as the 12-month follow-up what that group one was feeling and showing a really good progression. So green is less than four out of ten pain scale, yellow four to seven, and then red is above seven as far as that pain. So it shows a nice progression of decreased pain even at the 12-month follow-up. Case two, we have a 54-year-old female who crushed her right hand. She has pain and swelling, numbness to the digits, went to the ER, had an x-ray, everything looked normal, sat home, and then follows up in your clinic. Same complaints six months later. So again, you go through your typical assessment, you decide that she has CRPS, go through your history, your physical, other testing that you may consider, and where does peripheral nerve stimulation fit in here? Do we do the injections, do we do the more invasive treatments, or can we maybe avoid some of those? So one of those areas you may be able to even do it before getting into some more of the invasive medications. This study was done in 1996 in the Journal of Neurosurgery. It was studied CRPS patients with symptoms in one major peripheral nerve distribution. Plate electrodes were implanted along that nerve for a two to four day trial period, and then if the patient got 50% of relief, then a programmable device was then implanted. They were followed out for two to four years. 30 of the 32 patients who were trialed did go on to receive permanent implants, and results showed that pain was reduced from an average of 8.3 out of 10 to 3.5 out of 10, with improvement in the patient's activity level. And something that I find really interesting is that 20% of those who were implanted who were not working prior to the implant were able to return to at least partial, if not full, works afterwards, which is really important, really, you know, exciting for our quality of life and functionality of our patients. Next case, we have a 73 year old male whose status post-MCA stroke, left hemiparesis, complains of shoulder pain. He did inpatient rehab, did great, had assistance from his wife at home. Main limitation for him at this point is his shoulder pain. So again, we go through your typical history, physical imaging, you do all the different testing, normal appearing male, he has a post-stroke shoulder, no asbestosity that you notice, but you do notice that he has a shoulder subluxation. And you rule out other causes of pain, you decide that this subluxed shoulder is his cause of pain. So again, is there a role for peripheral nerve stimulation here? The x-ray here was taken actually from a really interesting article in 2011 that showed subluxation on x-ray does have a correlation with ultrasound findings of supraspinatus tendinosis, which in itself is interesting, but I think we'll come in a little bit later to play, may have some future research on that as well. But important to note, 30 to 84% of stroke survivors do develop shoulder pain, very wide variety, but again, stroke is so common that this is a great amount of patients that, you know, there's only, has been so much limited studies on it and limited treatments on, you know, how to get the pain out of the shoulder for these people and get them more functional again. So a peripheral nerve stimulation will help in, you know, can we put it in this area to hopefully avoid some of those other more invasive treatments. This study, the multi-centered study published in Neuromodulation Journal in 2017, post-stroke patients over the age of 21 who are over six months post-stroke with hemiplegic shoulder pain that was refractory to other treatments. They used ultrasound guidance to place a percutaneous lead to the axillary nerve and provided stimulations at the midpoint between the middle and posterior deltoid of the affected shoulder to create muscle contraction. This stimulation was a sham for three weeks after placement and then they returned at three weeks and the device was then activated and turned on. At the end of the total of six weeks, the lead was then removed and success was determined to be a reduction in pain by at least two points on the ten point scale. If pain returned within six months of the trial, then a permanent device was placed at the same location and the patients were followed out to two years. 16 of the 28 patients had relief with the percutaneous implant, 5 went on to receive the permanent implant, and outcomes showed improvement in pain and improvement in external rotation for the range of motion as well as improved quality of life. And then as we can see on the graph that those who were implanted at even the two-year follow-up did have great satisfaction. So impression of change, how the patients felt about the procedure did greatly improve even at the two-year part. So showing here that patients like it, which is always a good thing too when we're talking about different types of treatments. All right, so kind of deviating from our case load here real quick, just wanted to throw in some new therapy uses for the peripheral nerve stimulator devices. The study showed that we do get improved pain control when we apply the device to the suprascapular and axillary nerves. And so this led to some ongoing research for non-hemiplegic shoulder pain, including pain that's related to impingement, rotator cuff tears, or significant osteoarthritis of the glenohumeral joint. And multiple case studies so far have showed a great improvement of pain that is lasting, and we do have some ongoing research at this time just for shoulder joint pain, not necessarily hemiplegic pain. So that's very interesting, some newer research and newer treatments going on there too. And one of those studies published in 2014 in the Neuromodulation Journal, I'm not going to go through all of this, but essentially working off the idea of the prior study, the axillary nerve was stimulated for three weeks in ten patients with chronic shoulder pain, and outcomes showed improvement of pain, improvement of abduction range of motion, and functional ability at 12 weeks post-trial. So again, very important for getting our patients more functional again, as well as reducing their pain. Our next case is an 87-year-old female. She presents with right knee pain for a long time. She's very active, but this limits her daily life. So pain limits her quality of life. She's, you know, go through your normal history physical, very well-appearing, normal weight female. She has intelligent gait, pain along the joint line. Take an x-ray, shows significant osteoarthritis. Osteoarthritis is one of the leading causes of lower extremity disability in older adults. Hip and knee arthritis has accounted for a 2.4 percent of all years disability, and that's, you know, really important for as our population is aging that, you know, where this is becoming even more of an issue. 14 million people in the United States already have symptomatic knee OA, and it's a rapidly rising cause of disability and an increasing health care burden. So we need different things to improve this. Multiple treatment options. Obviously, we can always debate the efficacy of different types of injections and who they're appropriate for. And replacement surgery may not always be an option, whether it be because of, you know, patients other medical issues, they may not desire to undergo surgery. So then what? Or if, you know, they've had surgery and they still have knee pain, yeah, then what do we do? So can we put it before medications and other supplements, before injections, or maybe even after or around surgery time? So, you know, acutely or, you know, people who still have chronic pain after knee surgery. So this study is a feasibility study done in 2017 Journal of Orthopedic Research. Five subjects who were anywhere between 8 and 58 days post-op of total knee arthroplasty who still had pain that was uncontrolled by oral analgesics. So a percutaneous peripheral nerve stimulator lead was inserted with ultrasound guidance to the femoral and sciatic nerves of the post-op knee. Outcomes showed decreased pain at rest, so an average at 93%, with pain during passive and active range of motion also being significantly decreased. The leads were then removed within two hours of testing as it was just to see feasibility-wise. And then the ultrasound image there shows the lead being placed for the femoral insertion. This study was then followed out with and published in 2019 in Neuromodulation Journal, where seven subjects who are planning to undergo total knee arthroplasty had femoral and sciatic percutaneous leads placed seven days prior to surgery. The leads remained in place for six weeks post-op and then were removed. The results show that within the first week post-op, the average pain score were less than four in six of those seven patients. And four of seven subjects stopped opioid use within the first week. So that's really important for our current epidemic with opioids, giving people other options and better options rather than having to continue to use opioids. At two weeks post-op, six of those seven patients returned to pre-op level of the six-minute walk test. And then we had an average improvement at 12 weeks post-op of over 126% improvement in the six-minute walk test compared to pre-operatively. So again, functional improvements, quality of life, getting people back better and faster after their total knee arthroplasty. So a nice functional improvement along with pain improvement in these subjects. Again, kind of pausing, here's some new therapy uses around the knee for the peripheral nerve stimulator device is that the post-op knee studies showed improved pain control. And so therefore that concept was kind of shifted for earlier. So can we use it pre-surgery to treat the knee osteoarthritis pain? And so again, targeting femoral sciatic or just the saphenous nerve itself. And multiple case studies again are showing improvement of pain in the osteoarthritic knee. There's some ongoing research at this time as far as who and when you may work best for, but it is very promising. And at the same time, you know, shifting up farther out, you know, post-op for patients who have had total knee arthroplasty and using this long after they've had surgery. And again, still having really good improvement of their pain. So again, more research is going on in this area, but it's very exciting to give people another option for their knee osteoarthritis pain. So in general, there are some other treatment areas that we are focusing on. It'll be low back, hip, elbow, intercostal pain, ankle joint pain, post-op shoulder pain, similar to, you know, how we did it with the post-op knee. All very interesting and all, you know, very exciting uses that are being investigated for with the peripheral nerve stimulators. Specifically mechanical low back pain, we're kind of expanding on how we think of that and how we treat these areas that are not classically neuropathic pain pathways. And so there were, you know, challenging our entire understanding of, you know, what that actually means and how those nerve pathways work to create pain and why we can treat nociceptive pain with a neuropathic treatment. So one of those new areas, the axial low back pain, does have some really compelling studies. This one was published last year. It had a case series of nine subjects with chronic axial low back pain. A percutaneous peripheral nerve stimulator was placed to bilateral medial branches of the dorsal rami nerves at the source level of the patient's pain. So you can kind of see in that picture to the right there. The leads remained in place for one month and then were removed. Subjects were then followed out to a full year. The results showed that 67% of subjects had overall 50% pain reduction at the end of treatment and a significant reduction in disability and analgesic use. So it's a very exciting, you know, again, decreasing medication use, improving our patients function and quality of life. In 12 months post-treatment, 83% of patients reported improved quality of life, with 50% experience significantly reduced disability on the ospestry scale. So again, a functional improvement that has been, you know, shown going forward. So as, you know, some take-home points, as physiatrists we care for the whole person. We like to restore functionality and quality of life for our patients. The peripheral nerve stimulation technology has made significant improvements, especially in the last couple years, and can be used for a large variety of problems that we as physiatrists treat. Given our background with those patients, we are uniquely suited to use this technology and fit it into our current treatment protocols. There is ongoing research in multiple areas on how to use it, what to use it for, and some exciting new topics that we can, you know, look into. And I did put in some extra studies and further research in the next few slides, as far as our references, that if you want to take a look at, there's even more research out there if we need to. Otherwise, thank you, and I'm going to hand it over to Dr. Spinner. All right, thank you. Wonderful, wonderful talk. It's a perfect segue into what I'm going to be going into now, so let me get this open for everybody. Okay, so I'm going to discuss neuropathic indications for peripheral nerve stimulation. There are about four or five well-known randomized controlled studies currently now on the market that discuss different devices and indications and usage and how we got FDA approval for a number of these devices. I'm going to steer a little away from that and specifically talk about a couple cases and go through some of my ultrasound pictures to sort of actually show our fellow physiatrists what is it that we're looking at, what is that we're doing, how do we go through the algorithm, and what do we really see? So when we're actually doing a procedure, what does it look like? So disclosures, I did an ultrasound book years ago, and I do ultrasound training essentially for the PNS spectrum, and I'm a faculty for World Academy of Pain Medicine United, which also partners with numerous organizations basically for ultrasound and fluoroscopic training. Okay, and I'm going to do something a little different. I'm actually going to specifically show everyone some of the devices. I'll call them by their names. There will be no favoritism, but it's important to actually learn and see some of the nuances between what's on the market, and there's more on the market as well. In addition to what you'll see listed there, there's other, like Nainstay and StimWave, so there are other other companies on the market that certainly everyone should become familiar with because each patient that you see is going to have different requirements, and it's important to learn the intricacies of these devices. Okay, so why peripheral nerve stimulation? So for me, ineffective prior treatments, right, so physical therapy, neuropathic medications, you know, interventions, they just don't seem to have enough effect on most patients. Now, that being said, you know, for many neuropathic medications, I'll still do a nerve block, maybe a series of nerve blocks, and if patients do well, you know, if a small dose of gabapentin does a trick, I'm happy to stay there and we don't proceed further, but that's often not the case, especially once the patient gets to us. As far as the opiate bucket, I'm going to leave it there. We know that long-term use and increasing utilization of that is not the way to go, okay. Invasive surgery, so in some ways surgeries, you know, send us and keep our doors open, but that's not the best approach for this. You know, we really want patients to get better without requiring invasive surgeries, and I will tell you a lot of the cases that I do come from peripheral nerve surgeons that really understand this, that there's not a clear mass or something restricting a nerve that should anatomically be fixed. They send it over, right, so we can neuromodulate these nerves to get some benefit, okay. So peripheral nerve stimulation is minimally invasive. There's no more or you really don't have to do open dissection. There's some can be sometimes some blunt dissection but no more really truly open dissection to a nerve. It really is very relatively low risk. I won't get into all of it but I don't hold blood thinners for cases. It's low risk. It's not in an epidural space. It's not spinal. Obviously it's a normal standard of care as far as antibiotics, sterile preps, things like that, okay? And it definitely was applied earlier in the treatment algorithm. We know from numerous studies that waiting to treat a nerve disorder that becomes centrally mediated as a pain syndrome doesn't work well. It's hard to come back from that. So it's definitely moved up our treatment algorithm as far as how to do this. I'm going to specifically talk about a few neuropathic targets, okay? So I'll show you slides, actual pictures, my ultrasound pictures for two different sciatic nerve cases although I'll talk about one but I'll show you slides and two to show you some different ultrasound approaches. A femoral nerve case, a radial nerve case, and then I'll just briefly talk about two more without the ultrasound pictures but just to highlight and mention some nice stories regarding this, okay? So my first case is sciatic nerve, okay? So it's interesting. So it's a 50 year old female who came to me with severe pain down the leg. So the diagnosis is perineuropathy but sort of. It's not exactly but sort of. Okay, so patient noticed a bump on her leg. She had imaging that revealed a small mass and she underwent surgery to remove the mass, okay? So the surgeon didn't do a prior biopsy and cut the mass out intraoperatively and the mass turned out to be a schwannoma. So in the process they did a schwannoma perineal nerve resection. So left this woman with no with a tibial nerve but no perineal nerve in the posterior thigh. Otherwise a very healthy, normal, individual, professional, working. No other medical history to note. As far as disease treatment history, immediately as we'd expect, developed severe neuropathic pain, dropped foot. The patient unfortunately then had to undergo tendon transfer surgery to eliminate the drop foot so at least she could ambulate more normally. She was convinced by a neurosurgeon to have nerve graft surgery which did not alleviate any of her symptoms. She had nerve blocks and she's not interested in these spinal interventions after this. She wants to limit interventions and certainly not go towards a spine. She's tried every neuropathic medication. I'm not going to run through them but you know they help with the pain ever so slightly and she doesn't want opiates. She's not interested in that. She wants to go back to work and be a normal person. She doesn't want to go down that road. Okay and this was interesting to me. So she made a very clear statement to me and she first met me in the office. If cutting off my leg would stop the pain, I will gladly do so and move on with my life. That's a very powerful statement to hear from a patient. You know we all hear that once in a while. It's not a very common something to hear but that's really someone who's really in very severe pain or needs help. Okay so in this case I use a Sprint device and I'm going to show it to you and then I'm going to show the other devices we go through and their indications very clear neuropathic disorders and you can read them there. Okay more importantly for us here is the lead. So what does that mean as far as doing an implant? What does that look like with ultrasound because that's what we're going to look at. It's a very small micro lead which has a big surface area as far as doing a circumferential field simulation around the nerve. Okay I'll give you a little close-up of what that looks like and that's the little microstructure allows for some ingrowth of the lead so it holds in position. Now that's a 60-day lead that that stays in and gets pulled out after 60 days. Now this is an ultrasound picture of the posterior thigh and the middle structure here is a sciatic nerve that we're looking at here right in the middle. Okay the femur below, tendon, muscle, tendon, soft tissue around it. Okay this is an example of the stimulation needle as we go in. So in this case I literally go in there and I pick up the nerve. Now this is not part of the nerve that was resected. This is this is proximal to that. Okay again it shows you that lead as it goes as I'm holding the nerve and going past it and then here you go this one. So this is where the nerve graft site is. So the black circle here is a nerve graft where the perineal nerve should, perineal side of the nerve, the sciatic should sit. On the left here is the tibial and this is the stimulation lead below. It's interesting as what it would be expected there's no stimulation of the perineal nerve but she liked the stimulation of the tibial nerve. She got a very classic stimulation along that tibial distribution. And as we mentioned before Dr. Desai before mentioned sort of the old spinal cord stimulation sort of mindset. She liked the the buzzing sensation of the stimulation that distracted the other pain. So the very classic sort of sensory afferent mindset. She did very well with that. Right so that that was something that was very good for her and so she ended up doing well with doing well with this implant. Okay now this is a different case. I won't get into the case but just to show you the ultrasound pictures. So this was the prior one was an in-plane approach showing how to actually target a nerve. You clearly see the nerve and you get your needle stimulation probe right to the nerve. This case is a little different. This is a different sciatic nerve case where here we see the tibial and perineal nerves. This is the other leg before everything's reversed here. The popliteal vessel is below. Okay and what's interesting here you could measure cross-sectional areas and this is a case where I went out of plane to target the sciatic nerve where you can see a needle tip but just a little hypercoic dot on one side and you can measure that distance from the nerve. So you can safely get at a nerve, measure that distance, be a certain distance away and actually sort of inch although we're talking about centimeters and millimeters here, closer to that nerve and stimulating around the nerve to get the desired coverage in a dermatol sensation or mapping that you'd want. Okay so here's a video of what some that would look like from one side to another right where the nerve is here and here I'm going to play that again. A little twisting of the bevel you can see the soft tissue move next to the nerve. Again here now with color flow you can see the vessels, the sciatic nerve out here and then again I'm doing one more time a needle rotation again next to the nerve you get a sense of that distance away from the nerve. And here we actually get a trace the nerve, excuse me, trace the lead as it's going towards and away from the nerve you actually see placement as you get down to a nerve. So with the sciatic nerve in the middle we do first peroneal lead tracing here and you look for a little hyperchromic dot as it slowly comes up there you can follow those arrows. I'm going to play that one more time. So along the left of your screen you'll see a little again a little white hyperchromic dot. So you can trace the lead. Now these are very thin leads but you can clearly see it with ultrasound and get to the nerve safely. Now I'm going to show you the other side again a little twisting of the bevel on the on the tibial side of the nerve and then here it's a dual lead. I place leads on both sides of the sciatic nerve to bookend the nerve. You don't always have to do that but you could certainly stimulate around the entire sciatic nerve. You could do dual stimulation around single nerves basically if you like as well. So here you'll see a hyperchromic dot on the screen on the right and here on the left and we're going to trace those as they go down towards the sciatic nerve and then they stop adjacent here and here almost looks like Texas Longhorns next to the nerve. Okay and then here another one there towards. Now we're going to go away just to show you one away. Right and you can trace the leads here and here going away. What's important with this is they have to be able to use ultrasound to identify the nerve, the vessels and you could do these safely in a lot of the areas of the body. So this is some examples of a sciatic nerve stimulation. The next one's femoral nerve. It's a lot of people get nervous about femoral nerve because of the underlying anatomy in that area you know the vascular structures. We're not we're not afraid of it. I think if we use ultrasound smartly and cautiously we could certainly get to and around the nerves in a very safe way and my mantra has always been the bigger the vessel the better because with ultrasound and color flow you could clearly identify structures that you want to avoid and be watchful mindful for. Okay so here we have a fifth-year-old man with anterior and a little bit of medial thigh pain. I we think he has anterior femoral cutaneous neuropathy. It's a star signing event. Okay very sensitive to touch, clothing, sharp burning, stabbing pain, very neuropathic in nature. Now he does have a history of diabetes and obesity potentially a diabetic mononeuropathy versus the size maybe of the patient maybe a compressive neuropathy as a nerve crosses the hip. Imaging didn't reveal a specific nerve compression and this is not a nerve that's easily tested for electrodiagnostics to really figure out but he does the patient is certainly suffering with a lot of neuropathic pain. What's said to me he's had prior nerve blocks before, pulse or radiofrequency ablation, mixed responses. We're not going to denervate his femoral nerve right so that's not gonna be an option for him and again to put a spinal cord stimulator for this patient now he has a higher risk of bleeding, infection, nerve injury related to spine versus doing something in the periphery. So pain medication again he's tried all neuropathic pain medications. Now for this patient we use a different system with Nalu and so with this system we have four contacts here and a time lead for the soft tissue and an IPG and then a therapy disc you'd wear on the outside. So he underwent a wear trial with this therapy disc we found a good spot he'd like to wear and then I chose this because of the contacts as it would cross over the nerve as far as sizing because it's difficult to identify the anterior femoral cutaneous nerve but we knew the fascial plane and above the femoral nerve where it would sit. Okay and this just shows some of their you know features of PNS and SCS software package of using some SCS stimulation in the periphery. Okay so now the ultrasound picture. So here we have our femoral nerve vascular structures, our nerve, artery, vein to the side. Okay so this is lateral on the left, medial on the right. So we came a lateral to medial approach. Okay another picture of that there. The vessels here with a color flow and then here's the needle as it comes in and we're coming in right here right on top of the femoral nerve with our vessels here to the side. And here's another picture here coming in over the top now a little higher getting right on top of that nerve almost towards that sort of fascia that I could set a space through here in that fascial plane. And then here's a video of the of the lead popping out right here. So I'm going to play that again for you because you could see the lead just as it's sort of coming out into the soft tissue just over the nerve and adjacent to the artery here. And here is a picture you can see the needle here but the lead was cut is coming in over top of the nerve so we can identify and get simulation over different parts of the nerve because we know that it's not the whole nerve that's affected. It's a specific bundle within there. And here is a video simply of the lead itself scanning the lead as it comes in and comes over the nerve here. I'll play that one more time. So it's this white line as it's coming over the top here and it stops up here just adjacent to the artery and the nerve is sitting right next to it okay. So a nice safe placement. This gentleman is again doing very well wearing pants, less medication. You can touch that area now without him jumping. When I first came in I touched his thigh and just chatting with him and he almost jumped off the table. You know so now he's not doing that. So it's a good outcome. So now this patient was actually sent to me from someone who wasn't doing, in a sense pediatric, but this is a 17 year old female okay with a radial neuropathy. So she underwent an elbow surgery over the dorsal aspect of the arm after an accident okay. She began having burning and tingling pain along the dorsal forearm. So sort of in that sort of radial nerve distribution whether it's posterior cutaneous nerve or forearm or the arm itself higher up versus exactly radial nerve, we know it's along that spectrum right and that's gonna be the neural circuitry to help her okay. Otherwise healthy individual developed immediate neuropathic pain after the surgery you know and sort of in a classic sense the surgeon says everything went great with the surgery there's nothing wrong here. Go see pain, go see physiatry, go you know we're done. So what do we do here right. So she had pain with soft touch and she was interesting she started to have a little trembling in the arm which she didn't have before okay. It was on numerous neuropathic medications again. A young young patient not wanting to do opiates and what's interesting when you talk to her really very nice still a kid teenager who was doing fine in school before but now started to miss school because of the pain. You know it's hard for her to sit in class, hard to focus, getting a bump into, wearing a bag right. So it's now really becoming not just a pain issue becoming a life problem for her okay. So in this case we chose to use Bioness. So it's a 15 centimeter lead with with three small contacts and a receiver and a gel patch and a patient remote so you could turn it on and off like all the other ones when you want. Okay so she opted for a permanent device because she didn't want to undergo you know numerous treatments and just wanted to be to be done with it. So this is just a quick picture again RCT study with this FDA cleared for neuropathic indications below the neck. There's a quick sort of picture of what that looks like with an implanted lead EPT and a patient programmer. All right so I'll go go past this one. Okay so we target the radial nerve so this is we have two videos here so both radial nerve. The one on the left here is the radial nerve at the spiral groove. Okay and here first is is a spinal needle with here stimulation probe that's blunt tip coming out. So I'm going to play this and you'll see that I'm using the blunt tip here to push and get under the radial nerve. So I'm clearing a little space here between the radial nerve and the cortex of the bone because that's where I want to park my lead. I'm going to park my lead and sandwich it between the radial nerve and the humerus. So now here on the right is a video of the lead itself and it's a little hard to track but I'm going to play it a couple times. You could track a lead this wire as it's coming down at the implant that's coming down with the with the electrode sitting on this side of the nerve as the left as the remaining part of the wire comes off to the right. So we'll play that again. You can sort of trace this as it's coming down the electrodes stop right under there right under the nerve. So we're literally hugging the nerve onto the electrodes. So if you notice in all three cases I presented we're getting right on the nerve direct stimulation to the nerve. I'll be glad to report that she is back in school. This is did this case before COVID. She was back in school before hopefully she's back in school again now and definitely happy and actually I saw a couple of her friends who are in pain as well since this time. Okay now I'm not going to get into the slide for these but I just want to show how remarkable this could really be for a lot of patients. This was a patient who had a stroke and this is just a video showing a motor stimulation and fixing that sublocked shoulder right so that's that's a glenohumeral joint prior that was sublocked. Now the motor stimulation of the deltoid actually puts the shoulder back in place. This is super exciting for a lot of us in the physiology community and here you see that subluxation that was there. I'm gonna play this one more time just to show everybody. Right so subluxed shoulder. Here's the head of the humerus and it goes back in right there. And what's nice with this is programming available to do intermittent motor stimulation along with sensory to really help these patients. Okay there's a plethora of indications. This was a patient of mine that had an obturator nerve neuropathy which is not very not very common. So here this was presented at NANS last year by some of my residents Dr. Mazzola and Dr. Mohamed. And so here we use ultrasounds to guide the electrode underneath the femoroneurovascular structure and then we switch the fluoroscopy here. So here's the ultrasound. Here we marked our spot at Dr. Freeman. We used ultrasound to come underneath the femoroneurovascular structures with our needle and then we switched here the fluoroscopy to guide the rest of the way down to Dr. Freeman. And these are the electrodes as they come out by the by the Freeman. And this is the final picture of the lead with electrodes by the Freeman with obturator nerve exits and the receiver into the thigh. So a lot of interesting indications. We'll do we'll do two more quick ones here. So we all see a lot of elderly non-operative patients. This first one is a 91 year old man who came to see me with severe knee arthritis with medial and anterior knee pain. So you can only walk a couple blocks. You know he's a history of CHF. He was deemed a board candidate for total knee replacement based on what they thought was cardiac limitations. Right. So and he had tried you know steroids, viscose supplementation. I don't know if I do not think he had any regenerative medicine techniques but certainly had a lot of medial anterior knee pain. And so came to me for another opinion. What else can we do? So with this gentleman we did a saphenous nerve stimulation and also an anterior femoral cutaneous nerve but distal along the top of the knee. And so this was a nice case where he after the implant he's able to walk many blocks, go to the store on his own and really lived his life to the fullest and unfortunately passed away. But nice gentleman who did very well. Interestingly the poor candidate for knee replacement ended up being inaccurate even though he did so well with in this case a nociceptive phenomenon but treated with going after the nerves with a neuropathic sort of technique. But really it was the knee pain that did not allow his ability to walk, not the cardiac condition. And then the last one I'll mention it was a 93 year old referred from a peripheral neurosurgeon with an auricular neuralgia. It was first time I had seen that. I was referred to me from some top people, top colleagues over at Columbia who had done some very good nerve blocks, pulsing of the nerve, very clear diagnosis. She came to see me, should have held the side of her neck like this almost the way a trigeminal neuralgia patient appears sort of holding their face. That very severe facial nerve pain but she would hold the side of her neck here and almost towards her ear. And so we needed to find a treatment for her. So we did again a peripheral neurosurgeon with an implant for her right along the auricular nerve as it crosses the sternocleidomastoid muscle. And weeks later when she came back in she's sitting there talking to me. She's not grimacing anymore. She's not holding her face anymore. She used to twitch. No more twitching. So it's a lot of very interesting nerve indication. So you know the moral of the story for me is really if you could target that nerve and you see it clearly with ultrasound you think you could get there safely. Peripheral nerve stimulation has really completely changed really I think our practice and how we go about treating obviously in this case we're talking about neuropathic disorders but even some nociceptive pain and non-operative non-operative candidates. So thank you for listening and I'm gonna throw the conversation back to the group.

peripheral nerve stimulation

physiatry practice

advancements

minimally invasive

case studies

ultrasound imaging

chronic pain

patient outcomes

physiatrists

treatment options