So good evening, all. My name is Alfio Mufade. Today is another episode of the National Fellow Online Lecture Series. This series is sponsored by AMSSM Online Fellow Education Subcommittee on conjunction with the Education Committee as well as the Fellowship Committee. Just in a couple of weeks, the next online lecture series will be on phalangeal and finger injuries. The speaker will be Jeff Leggett and moderated by Myra Liu, actually. It's with great pleasure that I have Dr. Danny Herman speaking today on transit neuropraxia and a couple of housekeeping rules before we get started. The purpose of this lecture is to serve as an adjunct to individual programs didactics. The goal is to have a direct access to a diverse range of AMSSM members and occasionally guest speakers, as well as also to assist with the CAQ examination preparations. Just a couple of things before we get started. Please remember to go on mute and turn your video off. Remember to submit your questions on the chat function. And at the end of the session, at the end of the talk, I will be asking those questions to Dr. Herman. After this program is completed today, please remember to fill out the evaluation. So, as we've heard of you, I'd like to have Dr. Danny Herman to take it on and lecture us on transit neuropraxia. Thank you, Danny. Well, thank you so much. I'm going to, well, I'm trying to get my screen share together. I was thinking to myself as I was entering this lecture and had gotten the invite from Alfie that I thought, wow, what did the fellows do to Alfie? What did they do to make him so mad to deserve me as the lecturer? Wow. I mean, you've only been fellows for a couple of months. Man, that's some quick work. Joking aside, I'm definitely honored and pleased to present today and give you my thoughts and some educational points on burners and stingers. And let's get started here. So, first of all, no disclosures, although I'm definitely disclosure curious. So, if you have any opportunities, particularly those that are lucrative, just let me know. And then just to give a brief outline, I'll be talking a little bit about the pathology of these transient neuropraxias, risk factors, presentation management, and then prevention. So, in terms of the definition, the definition is that this is a neurologic injury. It's typically transient. And you say, well, Dr. Herman, no doubt. That's kind of in the title, isn't it? Well, that's where the kind of what we know ends to a certain degree, because there's a lot of debate on where exactly these injuries are occurring. Some people say that it's within the brachial plexus and particularly in the upper trunks, sometimes kind of go down to the middle trunks, but primarily the upper trunks. And some people say, no, it's not a plexus injury. This is actually a cervical nerve injury and primarily in the C5-C6 distribution. And so, it's one of these cases where it's kind of like that old Miller Lite commercial where you got the one side of the bar is yelling, tastes great. And the other side of the bar is yelling, less feeling. Maybe I'm dating myself with that ad reference. But of course, part of the point in the ad is that, hey, it's both, tastes great and less feeling. And probably it's both in the case of transient neuropraxy as well, where some injuries are at the level of the brachial plexus and some are a little bit more proximal at the cervical nerve roots. Regardless of the case, typically speaking, you're going to be having your injury, side of injury is going to be in that upper cervical, upper trunk area. Although you can get involvement of other areas of the plexus and other levels. The plexus can behave kind of strangely and you can have kind of patchy distribution of involvement. That's very kind of typical of brachial plexus injuries. And depending on the mechanism of injury, you can even go down as far as involvement of the lower trunks and C8-T1, particularly if the arm is up in an AB-ducted, extreme AB-ducted position. So for the mechanisms of injury and how we actually get these injuries during sports, you can get it via direct compression at Erb's point. And so, you know, typically speaking, this is when you're receiving a blow right at the base of the neck where it integrates, where it ends and kind of goes into the shoulder girdle, right at that angle. And so here's kind of an example of a potential injury mechanism during a tackle. This running back's hip and kind of iliac crest region is kind of digging right into the base of the neck. Not out more towards like where the AC joint is, but really much more midline at the base of the neck and potentially providing direct compression to the upper nerve roots and upper trunk. We can also get a couple different mechanisms within the frontal plane. We can get a traction mechanism where we get our head tilted away from the side where we're getting hit. And we get traction, particularly on those upper nerve roots with that particular positioning. You can also get injury to the contralateral side with that same positioning where you're compressing the contralateral side. And typically speaking, when you're engaging in compression like this, this is probably more a nerve root injury, whereas on the opposite side, if we're getting traction, it can either be plexus or nerve root probably. And so here is a potential tackle for that. You can see that the Bills player here on the right is receiving a blow to the right side of the head from the opposing player. That's going to cause their head to be tilted over to their left-hand side, resulting in traction on the right side and compression on the left side. Some additional mechanisms of injury, we can get injury from motion in the sagittal plane as well. This is with extreme flexion and extension. And typically speaking, when we're looking in the sagittal plane with these mechanisms, we're typically looking at a nerve root injury at the neuroforamen. Classically, this oftentimes involves an illegal tackle like a spear, so the LSU player there on the left is engaging in a spear tackle where they're leading with the crown of their helmet into the player. And if you do that with sufficient force, oftentimes you will then go into a kind of a forced flexion position. If you do that with significant greater force, you can actually then cause much more serious catastrophic injury. This is why these spear tackles are now illegal. The player number four there who's receiving this blow is also getting that blow underneath their face guard. And that face guard, with that upward blow, that face guard really provides a really good moment arm by which that force can be applied good moment arm by which that force can be applied to lever the head back. And so you can see the player's kind of going into an extension position. So this is kind of an example of kind of the forced extension. And depending on the level of force applied with the spear tackling there, potentially something that would go into forced flexion, either of which can cause neuroforaminal compression. So that's a lot of different mechanisms. You have direct contact. You have a traction mechanism in the frontal plane. You have a compression mechanism in the frontal plane. You have compression mechanisms in the sagittal plane. You're potentially affecting the plexus. You're potentially affecting the nerve roots. It's kind of a bit of morass. And one of those cases where if you got 10 different doctors debating all this and in the same room, you'd probably get 12 different opinions. So there is a little bit of a fog out there in terms of what is the most important mechanism, what's the injury that is caused. There is some kind of potentially slightly emerging consensus that traction injuries are more likely to occur in adolescents for various reasons related to the fact that they tend not to have developed features such as degenerative disc disease or things like that that would make their necks more prone to compression. Whereas adults have probably picked up a little bit of pathology and are less able to kind of get into a position that would result into a traction injury. And so compression may be more common in adult athletes. But that's a little bit of a supposition. There's not really any data to support that position. So looking a little bit farther down at the neurophysiology in terms of what happens to the nervous tissue, we have three basic types of neuropathology. We have neuropraxia, axonotmesis, and neurotmesis. And so neuropraxia is just, you know, kind of an injury to the myelin sheath. You're not really getting an injury to the axon. This is going to be the vast, vast majority of the stinger injuries. The myelin sheath gets injured, and typically you can get remyelination relatively quickly over a short period of time and good prognosis for quick recovery. Axonotmesis is actually when you get axonal damage. And so there's damage to the axon itself and as well as to the myelin sheath. But the endoneurium and perineurium and epineurium and other supporting structures that are part of the nerve itself remain intact. And so there's kind of a pathway by which you can get a growth cone and potential growth to bridge that area of axonal damage and get recovery. But that does take some time, weeks to months. So the outcomes are going to certainly be a bit delayed. And finally, with neurotmesis, you're going to get injury to the entire nerve. So it's not just the myelin, the axon, it's also the endoneurium, perineurium, and epineurium that's going to be injured. And so in this case, you don't have sort of that ultra structure by which the axon can can bridge that gap very easily. Oftentimes, this is something that, you know, needs urgent surgical intervention to help with. And really, at this point, it's debatable about whether or not you can really truly call this a stinger or burner, because by their very nature, they're transient. You should be recovering. So this is really more, you know, kind of a brachial plexus, true brachial plexus injury or nerve injury. Thankfully, very rare, although I will say that I have seen it happen, or at least have seen people who have had it happen. When I was in college, I played one year of football before I found out that I was not good enough to play college football. But one of my coaches was a former linebacker at my school at UC Davis, and had was a really big hitter, but really poor form and suffered a very catastrophic brachial plexus injury during a tackle. And so I was able to and basically had a flaccid limb, a flaccid arm as a result of it. So certainly does happen. So continuing on with some risk factors from an epidemiology standpoint, obviously kind of how we're talking about this primary sports that we see this in is going to be in tackling collision sports such as American football and rugby. With American football, it's actually really highly prevalent. In collegiate players, approximately 50% report that they've had a history of at least one stinger with a very high recurrence rate, approximately about 80-85%. So if you kind of do the math there, you're looking at probably about 40% of collegiate football players saying that they've had multiple stingers. And that's probably an underreporting. A lot of these stingers, again, are very transient. They can last maybe seconds to minutes and may never get reported. Or a player may want to kind of obfuscate that they did have a stinger so that they don't have to leave a game or they don't have any negative effects on their playing time, et cetera, kind of like with concussions. The risk is higher in games, and that's very common with most of the acute injuries we see across different sports is that games are at higher risk than practices. One thing that's important to keep in mind, though, that these injuries are higher in the preseason. We're not really sure about why that is, but one thought may be that players are still kind of going through good conditioning and building strength. And so I want you to keep that, kind of pin that and keep that thought in your mind. We're going to talk about cervical strengthening a little bit later in a couple slides. Rugby is very similar. There's also data showing that some 30 to 40% of high school and collegiate players also with history of at least one stinger in their career. So this is something that if you have personal experience in football or covering football and such, it's just something that all players are very, very familiar with. Back in the day when I was playing high school football, we didn't really know concussions very well and didn't know them to respect them too much, but we knew about stingers. Everyone got stingers all the time, it seems. So it's something that's highly high incidence and prevalence in terms of lifetime history. I certainly can get this in other sports, though. Some of the more common sports that are outside of these tackling sports would be collision sports such as hockey, certainly with player-to-player contact, but obviously with player-to-ice or player-to-board contact. You can see this player is kind of getting their head shoved over to the right and with compressive depression of the left shoulder potentially resulting in either traction injury to the left or compressive injury to the right. Anything that you can fall from a height is going to be at risk for suffering these injuries, so gymnastics, trampoline, equestrian, horseback riding, etc. Anything with a potential for a fall like that. And then also combat or martial sports. But you can get other things like basketball. I have a couple in the slide or two. Lacrosse, you can get hit with a stick and cause a direct compressive injury at Herb's Point, Herb's Point, things like that. You can certainly be in across many other sports. So from a biomechanical standpoint or technique standpoint, again, looking at rugby and football, these are tackling sports, high risk during tackling, and so if you have a poor blocking or tackling technique, that's going to put you at higher risk for this injury. And so here's one picture I found. I'm not exactly entirely certain what's going on here. I hope it's that the kid's helmet's coming off and his head's not inside of it right there at that particular picture, but obviously not tackling with an appropriate form. Kind of would have his head down, obviously, may be spearing and had a forced flexion in this particular position. We want to encourage having a more heads up position. There's a whole training program for tackling called Heads Up Tackling that we'll get to in a second. In rugby, they want to encourage tackling to have the head as example A there on the left and not B. You want to have the head behind the runner and not in front of the runner. And so tackling with your head in front of the runner in rugby is associated with a much higher risk of a multitude of different injuries of the cervical spine, including stingers and burners. I'm not sure if you can really see there on the left, but certainly on the right, these are two cases of tackles occurring with the tackler's head in front of the runner, and so that high risk positioning. So there's certainly some anatomic risk factors, so central planal stenosis being the most prominent of them and probably the one that we're the most concerned for, particularly on the back end for players who have had either multiple injuries or have had injuries that have lasted for a long time. There's radiographic measures that we can take, and there's MRI measures that we can take radiographic measures that we can take, and there's MRI measures that we can take to assess for this. The most used and probably the most, you know, kind of famous, quote unquote, is the torque-Pavlov ratio, or otherwise known as the torque ratio. And so this is a ratio of the measure of the canal area compared to the width of the vertebral body. And so you see the ratio there, A versus B. And a torque ratio of about 0.8 is kind of considered as a cutoff for being pretty sensitive, about 90% sensitive for assessing whether or not someone actually has cervical canal stenosis. Unfortunately, there's multiple concerns with this. One concern is that it's very, very sensitive, but it has horrible predictive value. So just because you have a torque ratio of 0.8 or less, you really still may or may not have it. Now, if you have a high ratio, you're probably in the clear. Again, sensitive, it allows you to rule out. But that's not where things end. Again, thinking about that high sensitivity, low specificity, you're looking across sports, particularly in older athletes, mature athletes, pro athletes, they have very, very large vertebral bodies, which will then bring that ratio down. And so if you look across like NFL players, or players going through the combine, etc., there's very, very high percentages of players that have torque ratios of 0.8 or less, some 50% or more of athletes. And particularly prominent in the larger athletes, so offensive and defensive linemen. There's also a lot of variation, depending on kind of race and ethnicity characteristics, where the distribution of torque ratios is very different in white populations versus African heritage versus Asian populations. So we have to kind of take that into account as well. So it's a bit of a rough measurement, it's still used a lot, but you have to be careful with it. And it's certainly not something I would rely on. It'd be maybe a good first step to look at when you're working up a patient. And then there's MRI measurements, obviously, can be a bit more, you know, precise. There's a measurement called the Mean Subaxial Cervical Space Available for Spinal Cords, so the MSC-SAC, which is just horrible. Whoever came up with that needs a new publicist, because TORG and Pavlov, it's TORG-Pavlov ratio, you came up with this word salad of an acronym, and it's horrible. You should add your name on that. So I think they should have gotten TORG's publicist, but anyway. That is a ratio of the width of the cervical canal and the width of the cord itself. So that's kind of the ratio there. And this is taken in a mid-saggial, kind of midline view. But there's a lot of other measurements that can be taken and used for the MRI. And so again, even though we're talking about MRI and it's a bit more precise, et cetera, there's a whole host of different ratios that can be used. Some people say that, oh, all you really need is functional space, a functional reserve. And what they mean by that is just if they see on the axial view, they just see a ring of CSF around, no matter how big it is, they say, oh, you've got functional reserve. If they don't see that CSF, then they say there's a lack of functional reserve and that's stenotic. Other people say that if there's eight millimeters of space at any given level, that's stenotic. But different levels have different variations in terms of how stenotic they may be, especially relative to the cord. So again, there's a lot of controversy there in terms of what people end up using clinically and what people tend to rely on. So keep that in mind. Some other anatomical risk factors, so that's kind of looking at canal stenosis. We can also pick up a lot of risk factors as we age and undergo repetitive injury. So this includes things like cervical disc disease and herniations, as well as osteophytes. Those will kind of reduce the amount of space that we have at the neuroforamen and potentially increase our risk for compressive events. And remember, there's this kind of thought that adults have a higher risk of compressive events. Typically, you're not going to see these findings in kids, and so probably accounts for the thought that compressive events are less common in kids and traction injuries are more common. So here's an MRI you can see in this collegiate football player who's got several disc bulges and some degeneration there in the cervical spine, and they're probably going to be put at risk for stingers. Reduced range of motion, so players who have a history of stingers have been found to have significantly reduced range of motion and flexion extension, and particularly compared to athletes who lack a history of having stingers. So group differences, not predictive, but certainly is kind of part of the picture. You can also get some thinning of the epineurium and perineurium as you age, and so the thought is that makes the axons more vulnerable to injury, either compressive or traction injury. You can even get things like stiff supporting structures, so stiff denticulate ligaments. If you go all the way back to MS1 year and studying anatomy, remember that old denticulate ligament, but it can get a little bit stiff, and then it provides sort of a counterforce traction on the nerve roots when you're engaging in sort of a traction injury on that side. All right, so enough of this background and risk factors and such. Let's move on to what this looks like from a clinical standpoint, or at least from a coverage standpoint. Let's put it more on the sideline and covering a game. So on the field of play, typically speaking, classically speaking, you're going to see a player coming off the field of play holding a limp arm, and so oftentimes they'll be kind of hanging down. They'll be holding it, kind of rubbing it, rubbing the skin, et cetera. Here's a couple of basketball players, pro basketball players that suffered stingers recently. They're making a good show of it with their facial expression. They'll oftentimes be kind of shaking their fingers or kind of flexing it, like they're trying to get their feeling back. This was Marcus Mariota, who had a couple of stingers during one of his seasons there with the Titans, and when he got his, his arm just kind of hung down to his side. You can see there, and he would just sit there and flex and extend his fingers and kind of shake them a little bit. And then there'll be, you know, talking to you and the medical staff, et cetera, talking about numbness, paresthesias, and pain in their arm. Typically it's going to be on the radial side because, again, C5, C6 distribution is the one that's most prominent, and that's the dermatome that's going to be, you know, most heavily featured. So in examination, when you first see this athlete, your priority is to first evaluate whether or not they have a more significant injury than just a transient neuropraxia. So you really want to think about cervical injury, spinal cord injury, brain injury, and these things first before you kind of say, okay, you just got a stinger and we'll monitor you. So if they have any sort of symptoms of concussion or any sort of altered mental status, you have to be certainly a bit cautious with this because they're going to be a poor historian, all right, and they may not be able to either engage in telling you what they're feeling as far as, you know, neck or peripheral issues, or they may not be responding to, you know, your physical exam instructions as they should. If they have significant cervical pain, midline tenderness, loss of range of motion, pain with range of motion, you should be thinking about cervical injuries, you should be thinking about potentially any sort of danger to the cord. And then if they have involvement of more than one limb, you got to be thinking about potentially spinal cord injury. So having a combined injury such as getting traction on one side and compression on the opposite side at the same time, even though it can happen in the same blow, is thought to be really rare. And so when you get that, you have to be thinking about what's called the rule of twos and be thinking spine precautions and potentially getting out your board, etc. So the rule of two, that's not the rule of two from Star Wars about Sith Lord and the Apprentice, you big nerds. That is the rule of two or more limbs or two stingers in the same game. Those are kind of thought or kind of repeatedly said in the literature from an expert consensus opinion to be an automatic hold. These people are not going to go back into the same game. So the most important of those is two or more limbs. You should really be concerned with potential spinal cord involvement. All right, so continuing on with this initial management, we're removing them from play and we're assessing again shoulder, spine, pain, range of motion, etc., neurovascular status, looking for any of those red flag signs, but also establishing a baseline of the patient and seeing where they're at in terms of their symptoms and their exam. Again you're going to be paying particular attention to the C5-C6 distribution. So you're looking at again that sort of radial side of the arm down to the C6-6 shooter. I'm not saying that's the only thing that you look at, but that's going to be where the oil is to drill. As well as from a myotomal standpoint, you're going to be looking at C5-C6 and upper trunk distribution muscles. So shoulder abduction, elbow flexion are going to be two of your big ones that you're going to be looking at and comparing to the contralateral side as well. And then you're going to be monitoring them over time as long as there's no red flag signs that you need to kind of engage in a more elevated level of care. You'll just watch them over time and monitor their symptoms and their neurologic exam on the sideline. The vast majority of these will resolve very quickly. However, if you do get worsening, that should probably also prompt escalation of care. That should not be worsening, it should at least be holding steady if there's no red flag signs or slowly getting better. Again most stingers are transient. That's the title of the talk, transient neuroparaxia, and should resolve in seconds to minutes. And we'll talk a little bit more about what minutes are kind of good and bad in terms of considering return to play. Ah, here we are, return to play. So there's kind of different guidelines for different scenarios. Again, these are highly prevalent injuries in terms of athletes' histories with an appreciable incidence rate. And so there's kind of different scenarios that you have to think about when considering the possibility of return to play, particularly within the game. So if a player comes to you, they have the injury, no red flag signs, etc., and it's their first injury and it's rapid resolution, then there's not really any need for some further workup, imaging, hold them out for advanced imaging, things like that. And they can return to play in the same game when they're asymptomatic, they have pain-free range of motion, both of their cervical spine and their shoulder, and a normal neurologic exam. Now, within five minutes. So that is based on a paper there by Schroeder et al., is a kind of a Delphi consensus group of I think primarily comprised of neurosurgeons who basically kind of came up with different criteria for different scenarios. And they had about 85% agreement on this statement of, if they resolve within five minutes, they're good to go back in, but later than five minutes, we're going to hold them out until they have further workup. I think personally, five minutes is kind of a hard line or a tough line to sell. Five minutes is pretty chintzy. Personally, I go out to 15. And there's other people in the literature from an expert standpoint will say 10 to 15 as well. So that's kind of a green light. These people can go back in. Certainly five minutes or less, again, I would advocate for up to 15. So in the next set of cases, if you have rapid resolution, and it's the second injury within a season or the second injury across different seasons, this is kind of more of a yellow light. Now, depending on what paper you look at and what expert you're talking to, you may get people saying, well, if it's the second injury in the season, you should hold them out until you engage in further workup. I tend to lean a little bit more towards that, where if it's their second injury within the same season, I'll say, hold on, we got to take a look at this. But I'm not hard and fast on that. It kind of depends on what those two injuries were. So if they were two very short, very transient stingers within the same season, and they lasted less than five minutes or whatnot, I'm probably fine to allow for that player to go back in in the same game. If that first one was a prolonged recovery where we were not able to get them back to their baseline at the same game, maybe it took them days to weeks to achieve recovery before they could go back to play. And then later in that same season, they get a second injury, even if it's a quick resolution, rapid resolution, I'm much more inclined to say, okay, hold on, we're going to take a deeper look at this if we haven't already. So in these cases, consider holding the athlete out, even with rapid resolution, and consider imaging, electrodiagnostic studies, et cetera, for looking for other issues and what's going on, which we'll talk about in a bit. And then if you have prolonged symptoms, so you're outside of that five to 15 minute window, or if you have rapid resolution, yeah, they feel better, but it's their second one of the same game. I consider that a hard stop. That's a no-go. Going back in, we're going to monitor to you further, see how you recover, potentially look at imaging and other diagnostics after the game. And again, that's that rule of twos, okay, again, second injury of the game, that's kind of a hard stop. Whereas the other one is not only a hard stop, but it's probably you need to potentially consider elevating care, boarding, et cetera. So in terms of diagnostics, which we mentioned in the prior slide, things like imaging, we had talked about radiographs, the torque ratio, et cetera. You want to get flexion extension views, but again, those torque ratios are somewhat questionable value in terms of how much to rely on them. We talked a bit already about the sensitivity and the positive predictive capacity of that value. Then again, on MRI, there's multiple different ways to measure this. You have the horrible acronym again, that space available for the cord. You have this functional space or functional reserve, and so here's the cord occupying the canal, and you can see they have this rim of CSF around that cord. And again, you have certainly neurosurgeons out there and others that say, look, as long as you have at least a rim of it, you're good, and if you don't, then that's a hard stop. Some other can say eight millimeter diameter, but another thing you're doing here is not just taking measurements, you're evaluating for other pathologies such as disc herniations, osteophytes, et cetera, which may inform your level of care, particularly depending on what age the athlete is and what they're engaged in, and determining potentially treatment and rehabilitation. Don't just focus on the cervical spine. You may also want to consider a brachial plexus study as well. And then electrodiagnostics, they're not something that should be done immediately. You really kind of need to wait about 21 to 28 days prior to having someone complete that study, otherwise the evolution of the injury is not really seen very well on the electrodiagnostic study, but it can provide some prognostic information for cases that are taking a long time to recover, so for a few weeks. One thing I will say, if you don't have any experience with electrodiagnostics, and particularly the EMG electromyography component of that test, I do want to say that it's not the most comfortable thing in the world. You can get through it just fine, but it's not fun, and I don't know if there's been any studies on this to show level of acceptance of the test compared to age. But if you have these, I used to do these tests early in my career, and certainly trained on it in PM&R. You have these 65-year-old ladies and guys, and they just sit there and chirp about their grandkids and tell you about the last trip they took and stuff like that. It's no big deal to them. Whether that is just they're kind of more resilient, or maybe they lack quite the same level of pain, no susceptive fibers, I don't know. But getting that needle into their muscle and having someone poke around their muscle with it and activating their musculature with a needle in their arm just doesn't seem to bother them all that much. Whereas you get a teenager doing this, expect some grief. They do not like it. I don't know if it's a resilience issue, but man, they tend to be tough for the electrodiagnostician to examine. I will say there are exceptions. This is story time, so gather around, kids. I had an athlete who had a chronic stinger, and it was actually referred to me by Jason Zaremsky, one of my colleagues. I'm doing the study, and he did the nerve conduction portion, the kind of shocking portion just fine, but we got to the needle part. I'm just doing the first one, and he looks at me and goes, I might throw up. I've never had anyone throw up for this exam, but I dutifully get the bucket out and the trash can, and lo and behold, he throws up. I'm like, oh, man, okay, well, I start, and he's just puking his guts out into the trash can. I turn to the mother, and I say, well, we didn't get a full study here because we weren't able to do all the muscles that we want, et cetera, and he stops, he spits, and he turns to me and goes, oh, we're not done. I got to get back in the field. We got to get this information. We got to do this, and I'm like, okay, okay. I would do a muscle or two and stop, he'd puke, do another couple muscles, stop, and by the end, he was just dry heaving, but, man, that kid, Roman style, man, he got through it and got to the end of the study. You don't see that too often. Just know that this is not a study that your athletes are going to really be happy about. All right, so in terms of management, first of all, a little bit about rehabilitation. For these chronic stingers or stingers where people have had multiples, you can engage in some physical therapy, working on things like cervical range of motion. Again, those athletes who have had multiple stingers tend to have lower range of motion compared to athletes who have not had stingers. Cervical strengthening, so there's a little bit of argument here. I'm going to talk about this in another slide. You can certainly engage in strengthening, but it doesn't really necessarily have a whole ton of data behind it. Thoracic core imbalances, certainly creating a strong base of support in the scapula thoracic core for both the shoulder and for the neck, I think is important. Oftentimes you get, especially in the younger players who are in the gym, weightlifting for football, et cetera, they just work on the gloria muscles and work on the pecs, and they can get very, very pec dominant, and they're not really doing much with their scapula thoracic posterior chain, and you ask them to do some I's, Y's, T's, and W's, and they're shaking like a leaf even without any weights. That's something that I always incorporate into my cervical patients' physical therapy. It's really important, I feel, and can be very much missed to consider lumbopelvic and thigh strengthening contributions to biomechanics. I had mentioned the heads up tackling program, and so we'll talk about this in a second, but if you look at some of the positions that they want you to adopt, so here's the case getting down, you're supposed to use more of your anterior shoulder rather than superior shoulder to initiate contact. You want to have a heads up position, and you have to kind of get down into that athletic position then to kind of explode forward with your hit. If the kid is weak in their glutes and their quads, they're not going to be able to get in these positions very well, and what are they going to do? In compensation, they're going to bend at the waist, and they're going to put their head down. And so obviously, that's the position that we want to stay out of, not just for the burners and stingers, but we want to stay out of it for more catastrophic cervical spine injury as well. So you've got to make sure that they're able to, throughout the entire kinetic chain, able to get into good positions to engage in good biomechanics and good tackling form. And it's not just about focusing at the neck and focusing at the shoulder. There's no real clear rule for modalities. In fact, I'm gonna step on the soapbox here and say that if you remember one thing from my lecture, it's that modalities suck, don't use them. Pretty much every PT script I write says no modalities because there's not really much evidence in literature that they work for pretty much most or anything with a few exceptions. And otherwise, physical therapists love to use it because they can bill for it and they're easy to do. But so I'd keep that off your PT scripts. All right, so what about things like return to play and particularly this kind of question of stopping someone from finishing out their season or potentially even considering medical retirement? So this is pretty controversial. Three in the same season, there's some expert papers out there, expert opinions that say you should remove for the season. I'm a little bit more like consider removal. Again, it's all contextual. What are those three stingers like? Were they three stingers that were very, very transient? They resolved within seconds and they were throughout the season or were they three that, the first two you didn't even know about and they were transient. So you haven't even done any rehabilitation yet. You haven't intervened yet. And they had three little ones. Well, that's a very different story than if the first one was pretty significant, you engage in a lot of rehabilitation and then they had another one and another one despite your best efforts to intervene and prevent secondary injury. That's a little bit different situation than if you, if they're minor, if you didn't know about them, about the first two. Central canal stenosis is certainly something that is gonna be a sticky wicket because again, there's multiple different measurements. There's no real hard line about, hey, this measurement, you're out. And so there's multiple measurements and standards kind of muddled the water. Furthermore, the relationship between central canal stenosis and catastrophic injury is associative, but not predictive. So what I mean by that is if we look at individuals who have had cord damage with minor injury or people who have had significant spinal cord injuries and you look at their canal diameter, they tend to have smaller canal diameters than people who have not had those injuries. But again, that's group differences and it's sort of associative. When we're thinking about, say people who have had transient quadriplegia and transient neuropraxia to their actual, to their cord, and you take these measurements of central canal stenosis, whether it's a torque ratio or whether it's an MRI ratio, the predictive capacity it has is for a second transient quadriplegia. It's not for catastrophic injury. So there's not that direct link to catastrophic injury. Now, on the flip side, when you're running a study like that you're not gonna sit there and have an athlete do more than two. They might be able to recover and go back to play eventually after a single transient quadriplegia, but you're probably not gonna let them go on to a third. And so you probably don't have enough events to necessarily get the data you need in terms of catastrophic injury. So that's a very tricky thing to obviously to study and a very tricky thing to consider. Being conservative on that is probably best. And then there's considerations in terms of age, severity and competition levels. If you're a younger player and you have such as a disc herniation, you're probably gonna wanna take that player out and say, okay, we're gonna try to let this heal, try to let this recover. Whereas somewhere of a degenerative injury, the cervical disc in an older athlete might be treated very differently. Again, if you have multiple recurrent events and you don't have any significant stenosis, potentially that's a player that can get away with it versus someone who is having multiple events that does have some stenosis. And again, of course, we're in these, a lot of situations where collegiate athletes and professional athletes may have significant financial incentives that are causing them to make decisions that other people, younger athlete, more recreational athlete may not be choosing. So if someone is on the brink of providing long-term financial security for generations within their family, they may risk it for the biscuit. So let's see. There we go. Talked a little bit about biomechanics already. Again, heads up tackling. This is something that you can download an app, coaches should be using. And this is something that we're trying to implement on a general basis in the sport of football at a very young level to teach appropriate hitting, not just for, again, for burners, but also for more catastrophic injury. And then coming back to strengthening, I kind of teased this a few different times. Cervical muscle strength, there's not really any epidemiologic data that supports muscle strengthening for prevention of stingers. In fact, the only study that I'm aware of that looked at any sort of comparative differences is between, looked at comparative differences between those with a history of stinger and those that are non-injured actually found no differences. Although I do have some beef as far as how they did their measurements and how they standardized them. No real big differences. However, that being said, this is very much a common recommendation that is put out there for stingers and burners because there is a lot of kind of common sense to it. If you got a kid like this and that kid is receiving a lateral blow to their head, how well are they gonna able to withstand that blow and attenuate that force versus someone like this with a base of support in the neck just like that? So the other thing to keep in mind too is there's secondary effects here for cervical strengthening. There actually has been shown to have a protective effect as far as concussion prevention. So I would endorse cervical neck strengthening for these athletes. And you can do this in simple ways that you have a teammate, maybe you're pressing your head against their knee or pressing against their hand and they're resisting force in various ways. There's prevention programs that use that. You can use low-tech devices for neck strengthening and then a little bit more high-tech devices. Actually, the Iron Neck is a pretty slick device that a lot of my PT groups in the area use. And finally, talking about equipment. So in terms of equipment, neck collars, various collars have been shown to reduce cervical extension. Collars include the cowboy collar as shown here. You can see an example of how it fits underneath the pads and kind of wraps up around the helmet. It's primarily designed to kind of fit to reduce extension, not so much the lateral bending. Whereas the Kerr collar is kind of designed to do a little bit more of both and has a lot more lateral kind of presence there in those lateral flanges. And so the Kerr collar actually does, is the only one that's been studied that actually reduces lateral cervical bending. Whereas the other collars do reduce extension, don't do really much to alter lateral forces to the neck. However, this is all lab-based measurements. There's no epidemiologic data showing that these collars actually reduce the risk of suffering a stinger or burner. However, I will say just from my personal experience, when I have an athlete who has had a stinger or burner, especially multiples, give them a Kerr collar. It works like a charm. I've never had someone who's come back to me after starting to use a Kerr collar. I really personally highly endorse them based on my experience. And this is just kind of ending with a couple of videos here. This is actually, again, Kerr collar or cowboy collar, you're gonna see a reduction in the amount of head motion there with that force that's forcing you back into extension. However, where the Kerr collar becomes important is gonna be this lateral blow. The Kerr collar does a better job of absorbing that lateral force compared to the other collars, which pretty much act mainly in extension. All right, so in summary, again, this is something that is a little bit messy, but for the most part, probably brachial plexus and nerve roots, depending on the type of injury, again, upper trunk, C5, C6 area, primarily in these collision and combat sports were primarily with tackling being the main mechanism of injury on the field, with risk factors being poor technique with tackling and blocking, cervical disc degeneration, reduced cervical range of motion, and increased amount of cervical stenosis. We wanna return these athletes back to play when they're asymptomatic with a normal examination within the same game. Again, five minutes is the Delphi consensus. I use 15. You wanna hold from play. So the criteria for holding from play with triggers for different diagnostic tests is kind of unclear, but I would say the exception is the rule of two. Again, if you have two limbs or more involved, or if it's the second stinger in the same game, that's a definite hold, potential escalation of care, and definitely you want to look further. MRI is more specific for central canal stenosis than the radiographs. Neck strengthening is recommended without much literature support, but I do personally recommend it. Correct tackling techniques are important, and the Kerr collar is the one that's been studied so far that works in both the sagittal and frontal planes to potentially alleviate both planes of motion for both compressive and traction injuries. All right, so that is the end there. I'll stop my share here, and be more than willing to take any questions. Thank you very much, Dr. Herman. That was spectacular. We have a couple of questions, and I'm curious to get some of your response or feedback to that. One question was specifically in terms of returning to play. Do we have to kind of stick to this hard-line deadlines and guidelines, or it's more best to kind of have the conversation with the athlete in terms of, after so many of these burners, what are the risks you have versus institutional risks? What do you have to say about that? Yeah, it's tough. So one thing I point out first is it's not like a hard guidelines or whatnot. All this stuff is really, for the most part, it's expert opinion. There are some consensus things out there in terms of like the Delphi consensus with that random group of neurosurgeons. I'm not sure how it was picked. I'll be honest with you. I'd have to go back to the literature. So this is not something that's like, oh, everyone uses this, or there's two main criteria that everyone uses. There's a lot of leeway, a lot of give and take, and it really depends on the individual circumstances, the amount of risks that the individual's willing to take, the amount of risks that you're willing to take as a physician treating someone who may be at risk for something more severe, and again, the institution. And in some cases, it's gonna be, there's certainly, I wanna say, I think there was a player for Clemson recently that kind of came back to play after like a three-year absence, if I remember correctly, because of cervical neck injuries, and really long give and take between multiple different physician groups and opinions as far as their overall risk to finally get back onto the field. And so again, there's not really a hard line at all. A lot of it depends on individual factors. What was the level of injury, injuries that ever occurred in the past, and what are the findings on the MRI and what type of findings? So it is definitely a lot of give and take between a lot of different stakeholders. But the second question that I have is, if you suspect somebody has extensive nerve injury, more than just a C5-6, are you removing the athlete from play, or are you escalating, because you're concerned about higher degree or severity of an injury? So I would kind of want to clarify that. So if I'm thinking anything that's central, so spinal cord, definitely am escalating care in that case, thinking about spine boarding, getting them to where they can get urgent evaluation, et cetera. If it's more that I'm not concerned about the neck, I'm not concerned about the cord, but I'm concerned about the peripheral injury, whether it's, let's say at the upper trunk, and I'm just concerned that it's more severe than just a simple neuropraxic injury, then yeah, I mean, plus minus on that. Let's say that I'm concerned that they actually had neurotimesis. I think it's probably unlikely that they're going to have neurotimesis in just kind of one area, but I think it would be probably pretty difficult to distinguish whether or not they had neurotimesis or just a severe axonitmesis on the sideline in just one specific distribution. I'm not sure if there's anything other than the level of pain that the patient is in, or maybe the mechanism of injury kind of being a very high risk injury, if it was witnessed, that would cause you to escalate care that quickly. Really, the escalation of care, again, is going to be for more concern for more significant cervical spine injury, spinal cord injury, or cases where you just don't have a good exam because there's altered mental status or something else going on that's inhibiting your exam. The one thing I'll add to that is at the end of the day, when you have a DIC or nerve or peripheral nerve issue, you have sensory, motor, as well as reflex changes. So I think the follow-up is if you have this deficits in terms of motor strength, I think the rule of thumb is you're probably not going to go back to that, to that sport in advance that day. So I think that's just another way that I think about it. I'm not sure if you agree with that, Dr. Herman. To a certain degree. I mean, you can have a neuropractic injury where it's, you know, obviously it's just sensory and they're getting that tingly and numbness and stuff, but you can certainly get a weakness that resolves very quickly. I've seen it before in the sideline, within a minute or two, they're like, you know, they're testing their strength and they seem a little weak. And then, you know, a couple of minutes later, they're a hundred percent fine. Now, whether it was because maybe the pain or the shock from the injury was causing some neuromuscular inhibition, it wasn't really true weakness from like, from the nerve injury, you know, that's debatable, but it really is what your exam is telling you. Again, I feel that if they're resolving within certainly five minutes, I give them 15 and they're resolved, no pain, normal range of motion, normal neurovascular status, A-okay. And it's their first injury, I'm fine with returning them to play. So just gonna clarify what the question, in the chat, they were asking, I think if it's more severe meaning it's taken a longer period of time. I'm assuming if they still have the weakness after 20, 30 minutes, probably would not return them. Yeah, no, 15 minutes is my limit. I'm not gonna go past that. And again, you have that Delphi consensus, they don't go past five. So like more prolonged symptoms, yeah, you're gonna hold on those and potentially engage in some longitudinal follow-up and potentially a workup of, you know, other issues that might be predisposing them to this injury. So I have one more question and I have one personal question as well. So the next one on the chat is, what is the most accurate physical examination for a brachial plexus injury? Well, that's a can of worms right there, right? So I'm gonna dodge maybe a little bit and point out a couple of things that you want to not rely upon. So in general, this is just kind of a broad-based, you know, piece of advice for all of the fellows and burgeoning, you know, fellows out there. You gotta really know, you know, sensitivity and specificity of your different exams and different tests and how they, you know, kind of inform your care and inform what you're doing. So for example, when you're thinking about potentially having a nerve root injury and you say, okay, well, let's do a Sperling's. Well, how good is a Sperling's? It's very, very specific, but it's very insensitive. And so, you know, if you have a positive Sperling's that, you know, that tells you something, but a negative Sperling's tells you nothing in terms of whether or not there's a nerve root injury there. So, you know, be careful about how you're interpreting these different exam signs and know, kind of understand their sensitivity, specificity, et cetera, and use other tests to help with your overall assessment. So, you know, personally, when I'm looking at, you know, nerve root injuries, whether it's, you know, someone with, you know, potentially a stinger or even in the clinic, I have someone who might have, you know, cervical radiculopathy or something like that. I tend to really lean into strength testing and I'm pretty picky about angles to make sure the moment arm's the same on both sides and making sure I have a valid comparison, making sure effort is there. You know, I'm very picky about that, about motor function and motor strength. I think that the sensory dermatomal testing is a lot more subjective and a lot more difficult to do unless you have, you know, filament wires and things like that. So, you know, I don't know if I would say most accurate, but I really go after muscle strength. Now, that being said, how strong, or to me, how weak do you have to be before you can actually test it manually and you can actually feel it manually? Well, studies would indicate that it's about 20% strength loss before you can really manually tell that someone has a side-to-side difference. So you have to be cautious and know the limitations of that as well. So you're never really relying on one test. And the physical exam kind of sucks a little bit in terms of our sensitivity and specificity. And so the result of that is you really want to know a lot about the patient history, what they're feeling, what the mechanism of injury is, things like that, that helps you lead to your diagnosis, but also have multiple tools in your toolkit when you're doing your physical exam, because relying on just one thing, there's not one great end-all, be-all test for any given issue. You want to have multiple tools in your toolkit that you can pull out at any given time. Thank you again, Dr. Ehrman, for the wonderful talk. As a reminder, if you've not filled out the evaluation, can you please fill that out? As a quick reminder, our next talk for the fellow online, our talk is going to be on Wednesday, September 27th on fingers and phalangeal injuries, and that will be done by Dr. Legend. Thank you very much, and everybody have a good night. Thank you very much for your attendance, and I appreciate your participation in the Q&A there. Thank you very much.

3rd Edition, CASE 52

3rd Edition

Spine

transient neuropraxia

burners

stingers

brachial plexus

cervical nerve roots

athlete injuries

cervical strengthening

diagnostic tools

American football

rugby