Thank you, and I'd like to thank the Sports Health and AOSSM for the kind invitation. And again, it's really exciting to see the Sports Health Symposium and some of the criteria that we're going to use for Return to Play. I am George Davies. I'm a professor at Georgia Southern University in Savannah, Georgia. My disclosures, I am the associate editor for the American Academy of Sports Physical Therapy. For those who don't know about the journal, by the way, it's one of the largest circulation journals in sports medicine in the world. Over 70,000 members, and it has over 2 million downloads a year, and we just got a big bump in our impact factor. So again, it's a pretty significant journal at the present time. My role today is to talk about Returning a Knee to Health, Progression and Warning Signs in the Early Stages. So since I'm a U.S. Marine from 52 years ago, I do have to have this disclosure, similar to many military comments. The opinions and assertations contained in this presentation represent the private views of the author, because some of this stuff I'm going to present does not have good evidence behind it. Nevertheless, as Dr. Spindler pointed out before, based on the evidence, that again, if a patient is going to ultimately have surgery, they should have prehabilitation. And there's some of the criteria that should be obviously addressed in the rehabilitation phase. So with that, when we look at rehabilitation, traditional approaches have been on the left side of your screen, and now what's really interesting with all the cognitive things going on, the multimodal interventions, et cetera, these seem to be the trends that are going on, and I'm going to address some of these as we get going. But again, there's no high-level RCT studies that have really compared traditional rehab to some of the newer multimodal cognitive training types of interventions. So one of the things that we have to keep in mind is returning a knee to health and the progressions. It is rocket science. So what we have to look at, it's predicated on continuous monitoring of our clusters of signs and symptoms to see how that knee is progressing, but furthermore, there's a whole lot more involved. Now I'm only addressing the very first part of rehab, and many of the other speakers are going to address all of these different concepts that you're going to see on the slide. But if we don't take care of the basics first, then again, none of the following interventions are going to be effective. So first things first. We all know that mechanism of injury using an ACL is a model, that it occurs literally in milliseconds. Well, we don't always have time to react to something like that. So very busy slide, but the point is, when we have that injury using the ACL as the model, again, it's a very complicated process to really get that person back to sports. We're going to address some of those. One of the examples, we certainly see the obvious things, the atrophy that occurs. But underneath the atrophy, there's many subtle things that are also occurring. And we're going to be addressing some of those as we progress along. So as you can see, we have to now start looking more closely at some of the psychological factors, the whole new area over the last decade of this neuroplasticity. We need to use better criterion-based rehab, and then on-the-field rehabilitation. So has our rehab really evolved to keep up with this? And again, I'm only going to do the original portion, and then all the other speakers are going to talk about the higher-level components. But at any rate, this whole neuroplasticity is the leading factor right now that's driving a lot of what's happening in rehabilitation. And there are many of the different factors that are being identified now in the literature, and we'll be talking about that. So early on, we need to focus more on some mental practice besides just getting strength, power, and endurance. We need to look at some of the external focus concepts, as well as looking at some of the contextual types of interventions. These are the five things that I'm going to address that we need to approach when we begin our rehabilitation process. So education, by far, is the number one thing. We know it's multifactorial, but education is number one. So we really need to get our learn on at this time and educate that patient. So the most important skill that we all have is communication with the patient. And frankly, we need to start looking more closely at the whole biopsychosocial model of looking at rehabilitation. So again, we all need to look at the patient-centered care, and then looking at how the patient perceives some of that. So as we look into that, some of the research is showing that this whole biopsychosocial model is really the key player in the ultimate outcomes with patients. And many of those things that are identified on the slide are just examples of some of the things that we have perhaps overlooked in the past and haven't put as much emphasis on. So with that, again, we need to get that injured athlete involved in the clinical decision-making early on, because there's evidence that shows clearly that it greatly influences the success of an outcome. So with that, again, we know about this kinesiophobia, something else that's been very widely discussed in the last decade. And again, there is some underlying neurophysiological basis for that. And again, we have to consider some of this as part of a rehabilitation. But interestingly, look at that slide. In 2003, there were no studies published on kinesiophobia. Now in 2021, you can see from the PubMed index that now there's 158 articles that have addressed kinesiophobia as one of the things that we now need to address in rehab. Now, what's interesting, we've put so much emphasis on kinesiophobia and the fear of injury, but Mark Paterno, who's going to be speaking a little bit later, interestingly, has just published an article a couple of months ago in the Journal of Orthopedic Research. And interestingly, what he has shown is the opposite effect, that those who are, again, more confident have a higher injury rate. And those that are more confident and pass the criteria for return to sport actually have a higher injury rate versus those who have kinesiophobia. So again, where should our emphasis be placed? Furthermore, we have to look. This is how the patient feels when they arrive at PT and rehab. So we have to focus on managing our patient's expectations. So on the left side, that's how the patient wants to progress. That's how we want them to progress. And then on the bottom is obviously usually how they do progress, as we all know. There's many other factors we don't have time to talk about, and I'm not going to emphasize them, but now with nutrition and sleep and many other variables influencing outcomes. Mental health. Recent article, again, in Journal of Athletic Training just a couple of months ago talks about some of the mental health issues. So this was literally just published two months ago in the Journal of Athletic Training, and it talks about this past COVID year and how it has sensationalized some of the different psychological aspects that patients have been perceiving. So the International Olympic Committee actually has a mental workshop, and they basically put emphasis not only on the physiological rehabilitation, but furthermore, that we have to look at some of the cognitive behavioral approaches. So it's not just anymore about rehab, rehab, rehab, but it's really something else. Additionally, we have to give time, time. All the other speakers have mentioned that. Again, biology is the limiting factor. Can't be rushed. Again, Dr. Rodeo is going to follow this presentation, and perhaps he'll talk about some of the augmentation with using some of the orthobiologics, but nevertheless, we always have to respect soft tissue healing. Now, back to the five major points that I'm going to emphasize. Pain. How do we deal with pain? Well, this is pretty nebulous when we start looking at it. Pain is personal. There doesn't have to be an actual structural injury to create pain. Pain is perceived up in the brain, as we all know. Now when we look at the knee area, it's so involved, and we're all familiar with Scott Dye's classic work where he looked at the neurosensory mapping of the knee and all the different structures that had pain sensations. So again, it's a very complicated area that may send some of these signals to the brain. But if we look at some of the acute management, look at our typical progression. On the left side is our typical acronym we've always used to treat the patient in the early phases is REST. And it's now progressed to the second or the middle, which is POLICE as the acronym. And now the approach is to go to PEACE and LOVE as all the different approaches that need to be utilized when we're starting to deal with that patient in the acute phases. So dealing with pain. Obviously it hurts. What do we do? Well, there's a multiple number of ways of treating it. So physical therapy has many interventions, as we all know, and we can see on the slide are several examples. And I'm going to just highlight a few. One that we also need to be aware of is this whole pain neuroscience education process. Pain neuroscience education process. Because again, when we have an injury, that's going to send signals to the brain. Then the brain's going to digest that, and that's going to set up that vicious cycle where the patient's going to perceive this. So the whole neuroscience aspect of how the patient's going to perceive the pain is critical. So the pain neuroscience concept, again, is going to address how the patient's going to reconceptualize dealing with the pain. So let's not overlook some of the basic things as well like that. Medication obviously is another area. As physical therapists and athletic trainers mostly in the room, we know we can use all these various modalities. And I'm going to come back to BFR in more detail and exercise in a little bit. But again, we're all familiar with all these various modalities. There's been a little controversy recently about the use of cryotherapy, still one of the better modalities. Again, many other modalities, lasers are being used commonly now, complementary therapies. But the emphasis ultimately needs to be on exercise. Everybody has said, again, Dr. Dudich, when he went through the patellofemoral, it's all about the musculoskeletal strength in addition to the multifactorial areas. So what exercises should we use? Well, this is one controversial exercise. Should we do full range of motion, open kinetic chain exercises like that? Or should we basically just have others try that in a short arc of motion? And is that going to be safer for the individual? So we can watch him do that exercise or not. Furthermore, again, interesting concept, British Journal of Sports Medicine, number one citation, meta-analysis of the literature. A new form of exercise therapy focusing on loading and resistance that increases patient's pain. So again, protocols that have pain response after the exercise, as long as it's not real significant, doesn't create a lot of other problems, again, can actually have better, faster short-term benefits with pretty good evidence to support it. So if we're doing core and total leg strengthening, again, it's important that we make sure we do it the right way and not mess up. And then, again, if we're doing something like that, again, we can do things such as isometrics, multiple angle isometrics, short arcs, submaximal exercises. So there's many, many different ways that we can address doing that. Many people like to do short arc squats. So there's many exercises that we can do. Now the big paradigm shift is here. Now instead of having them just do multiple angle isometrics, short arc submaximal squats, now we do decision-based exercises. So in other words, instead of having them just do the exercise, have them start doing different types of mathematical decision-making, having them do different angles movement quickly. Reaction-based, instead of having them just doing wall slides or something like that, then you can have them catching a ball, throwing a ball, doing different types of things related to the neural cognitive training. Here distraction-based things. So again, they're doing short arc squats, but they're also throwing a ball, and you can do things like a vector ball, which changes colors as it's coming at the patient. So there's many, many different variables now with the cognitive-based training that's going on for the neurophysiological changes. Then again, VR, virtual reality training, I think is going to become huge in the future as we know. Exercise, exercise, exercise, but what type? And this is an article in Sports Health that actually demonstrated the significant changes with emphasis on eccentric exercises and how it changes some of the actual functional MRIs of the brain. So again, and then lastly, meta-analysis just recently performed two months ago on BFR and significantly decreases pain. We're gonna come back to that in a few more minutes. What about a fusion? We're all familiar with that, but look at this guy. This was Philippe Guybert in Tour de France in 2018. Look at that knee. He had a fractured patella and he continued to cycle for 60 kilometers. Look at the size of that knee. So again, talk about a fusion. There it is. Well, at any rate, they're all the negative sequelae if we do have a fusion. So again, not only does it hurt, but furthermore, it's going to have degradation changes to the synovium. And recently again, it just published that the degradation changes with the elevated synovial fluid is going to affect the articular surfaces. So consequently, what Dr. Cole just talked about, in a mild stage, there's the initial progression of it. That's one of our motivated patients who's told he can't do weight-bearing during gait, so that's how he gets around it. So at any rate, you never know what some of those motivated patients are going to do. We also know that knee effusion causes muscle inhibition. We'll come back to that again because that's probably the key factor to getting patients better. What do we do for the effusion? All those modalities can be used. We can also do aspirations, or the physicians can do the aspirations. Range of motion. Once again, we have to get the range of motion. How can we get that knee straight after surgery? Once again, test, don't guess. This is an example, I think, whatever is mismeasured can be mismanaged. So again, if we look at the slide on the top, the patient's ham, the KF is actually on the table. So if they're trying to measure for a recurvatum, they're not going to get an accurate measurement. So we really have to make sure that we do our measurements correctly. So with that, again, this recent study in AJSM indicated, again, that we know only about 2%, but nevertheless, 2% over 3,000 patients that end up with a cyclops lesion. But the highlighted green area, the most important risk factor is, again, was an extension deficit early in a post-operative phase. So that's what we really have to address in getting motion. Dr. Shelbourne has also taught us a lot about how we can stratify this into different categories, and then the importance of getting extension and perhaps hyperextension predicated on the opposite knee. And then there's research that shows if you have an extension deficit early on, that it's going to be protracted. So one clinical pearl, when patients are lying down, the legs externally rotate. So if we do the passive hangs in that position, that's actually going to stress the posterolateral corner. So again, if I'm doing the stretching, it's important, again, to make sure that you block it and not let the patient externally rotate so they stretch the posterolateral corner of the knee. So what can we do? Well, there's several different things, and we use the concept of low-load, long-duration stretching, or TERT. So there are all the steps that are involved in getting the plastic deformation or the elongated motion. So we can start with a bike. Even if they don't have full range of motion, we can do partial range of motion. Then we can do sustained stretching. So there we have an active metabolic warm-up and an external heating warm-up. So we're warming up the structures to try to get that plastic deformation of the collagen tissue. Then there's different devices that can help us. There's an extensionator device where the patient can actually control their own range of motion. And then one of the things that's critical, obviously, as we all know, is patellofemoral mobilizations, particularly cephalic glides for extension. And I like to use a lot of the Mulligan's mobilizations with movements as we're trying to regain the patellofemoral movements. Furthermore, we can use instrumented-assisted soft tissue devices for some of the tissue around the knee. Key, however, is to gain dynamic stability of the newly gained passive range of motion. To have passive range of motion in a joint without dynamic stability is useless. So again, home program, they have to complement the low-load, long-duration. If they have limited flexion, there's many ways that we can do that with wall slides, with different types of straps, and different variations of doing different pulley systems, etc. Caudal glides for flexion. And then there's different devices that help us gain flexion. Also, importantly, even though we're having addressing the knee, it's important to look above the core hip area. And then, of course, look at the distal area. And then, as has been pointed out again in the last presentation, we talked about the whole dynamic stability thing. So look at the entire lower extremity kinetic chain. Lastly is arthrogenic muscle inhibition. The biggest problem. It's a very complicated area. So again, we know it inhibits the muscle. But how, why, and what can we do with it? Well, again, it's a very complicated area and affects everything. Here's a recent study. If you lose quad strength, that's going to affect, again, the weight bearing on the articular surfaces. That, in turn, is going to create the degradation changes to the articular cartilage. So whether that ACL has its own little brain or not, don't know. But there's numerous, numerous studies on arthrogenic inhibition. And furthermore, we know that it can last for a long time, upwards of a couple of years. So what treatments can we do? Well, we can look at the bottom and we can do all these different variations. And again, we can do things like the modalities that we've talked about. We can use therapeutic exercise. We can use different vibrations types of things. But exercise really is the key. Exercise is really the key. So that's just a schematic that shows on the left side we have different types of injuries. Then what are some of the neurophysiologic adaptations? And then lastly, what are some of the clinical implications of it? There are some of the things that we can do that are published in the literature to look at affecting this arthrogenic muscle inhibition. So, and I'm just going to highlight a couple of them. A study by Sanre Cote, he basically looked at arthrogenic muscle inhibition. And they looked at all the different things that were being used and basically found two things were the most effective. And those two things, interestingly, were cryotherapy and exercise. And again, it didn't matter whether it was open chain exercise, closed chain exercise, or whatever. They were the most effective. Moreover, we know that doing electric STEM early on to facilitate is very effective. But instead of just doing STEM and having the patient internally activate the muscle, ask them to do the cognitive training by doing external focus types of activities. So we can use the electro modalities to facilitate the exercise itself. We can also do things very kind of advanced, transcranial muscle magnetic stimulation. And this was actually published in Sports Health as a case study. And Dr. Voidus, our editor, was one of the authors on the study. So again, this is something, frankly, is that really doing brain doping? So at any rate, it's another option that can be used. BFR. I'm going to spend just a few minutes with this. BFR, again, we're all familiar with that now. It's a trend. And again, the literature shows the effectiveness of it. We've already said it decreases pain, and it's very important in increasing muscle strength. But I'm just going to take one minute, and I have to give kudos to our editor-in-chief. As you can see, Dr. Voidus, very laid-back, casual guy. Every year we have an annual meeting, and this is examples of his staff at the annual meeting as he's talking all the time. So we just try to hang in there as he's going on and on. And I said five years ago, I want to do a have an article on BFR. And Dr. Voidus, as you can see, that's wrong. There's no science. That's wrong. So my response. All right. So even though he's won many awards, he's in the Hall of Fame and all that, he is an outstanding editor. And the reason he's an outstanding editor is because he recently has also published one of the best RCTs on BFR. It shows the efficacy. And he's also recently published a systematic review on BFR. So kudos to Dr. Voidus for listening to his staff. So at any rate, here's the most recent study on BFR, by the way. It's just published two months ago. And again, what it shows, there's no question that it increases muscle strength and it decreases pain. So again, and there's more and more research. There's a systematic review that's in press right now in arthroscopy that again demonstrates the efficacy of doing that. Interestingly, in 1962, no articles on BFR. In 2000, there were 90 articles on BFR. Today, there's 10,493 and over 3,700 of those deal specifically with therapy applications. So again, obviously it's a huge trend. But I mentioned eccentric exercise before and the reason I'm mentioning it one more time, this article was published again in Sports Health that shows the efficacy of using BFR as one of the primary things to affect neuroplasticity of the brain. Now, we can also, here's an article talking about using kinesio taping with patients who have arthrogenic muscle inhibition. Notice the brighter the colors, the more effective. And not only do you tape it over the knee, you tape it over the whole leg. And maybe you tape it on the antagonistic muscle in the back. But sometimes maybe we're getting carried away with that too. So again, but nevertheless, and the future strategies again, the bottom line is what we're addressing now is this whole neuroplasticity. So a few more slides here that, again, it's a bilateral phenomenon that when we look at the injury rates, many times it's the contralateral knee that gets injured. And the reason for that is there's an individual morphometric characteristic between the two parts of the brain in the hemispheres. So again, recent functional MRIs have shown, again, that when we injure the knee, we lose proprioception. So then we start to rely more on our visual aspects. And consequently, we need to change that paradigm. So we need to start doing things where we're going to affect the visual field. So in other words, have them so they can't see things as clearly. So they're going to have to rely more on the proprioception rather than on the visual stimulation. And there's a variety of things that are published now that describe that. Because of the things that are progressing with VR, I think that's going to be huge. And the last thing with getting there is normalizing their gait. Now, that's all the very basic fundamental things we have to start with at the beginning. And again, the reality of sports, it happens in a chaotic situation. It's very complex. And that's what all the other speakers after the break are going to be talking about. And again, we have a lot of great information coming up. Now, what about warning signs? A few warning signs. Number one, there's continued chronic pain. If they walk like that after a leg day, if they have continued effusion, if they have a stiff flexed knee, if they have recurvatum, or if they have continued arthrogenic muscle inhibition, they're the warning signs. So in summary, using the ACL again as the model, 10 reasons sometimes why ACL rehab fails. Number one, lack of clinically applicable practice guidelines. Two, gap between research and clinical practice. Many athletes are not ready to return to sport when they are returning to sport. No criterion-based progressions. Low quality rehab. We're not addressing some of those on-the-field characteristics. And again, addressing some of these newer neurophysiological changes. But you're going to hear the state-of-the-art with all of our presenters later on the advanced phases. Many of the athletes progress too quickly during rehab. Poor compliance and motivation. Rehab is not targeted to the individual, customizing it to the patient. And it's not just the physiological aspect, as we talked about. It's the biopsychosocial aspects as well. Limited communication. And finally, the healthcare system limitations. You only have so many visits many times. So in summary, we've talked about some of the returning a knee to health in the early stages of just progression. Some of the things that we have to look at and we can do. And then a few of the warning signs that we have there. Takes a team approach. And certainly, patient selection, structured rehab together creates the key to success. So again, thanks to Sports Health and AOSSM for the opportunity to share this information. Thank you.

rehabilitating knee

warning signs

patient-centered care

pain management

exercise therapy

individualized rehabilitation