Hello, everybody. Welcome to Lower Limb Orthotics for Neurorehabilitation, Why and How. My name is Dan Moon. I'll be talking about the introduction, the biomechanics of human gait. Alberto Esconazi will be in a little later. He's still working on uploading his slides, but we'll all be here eventually. So please save your questions till the end, but we hope you will be able to enjoy this talk. We have a bunch of cases in the second half, but first let's talk about the biomechanics of gait. So as you know, the gait cycle is a serial pattern of muscle control and joint motions used to advance the body efficiently and safely from point A to point B. It consists of stance and swing phase. We have individual events, sub-phases as well, which these are further divided into. Now, as you recall Newton's Law of Motion, when one body exerts a force on a second body, there is an equal and opposite force in the opposite direction. So if you think about applying this to our gait, as a body via the foot encounters the ground, the ground exerts a force onto the ground and the ground exerts an equal and opposite force onto the body, which is called the ground reaction force, as you see there. Now, how does this apply to joint movement? Now if you think about when you're on a playground, if you had a seesaw on your playground, you can imagine when you apply a force on one side of the seesaw, there's a rotation in that direction. And now, if you imagine our ankle joint, the tibial-tailor joint, you can imagine this to be like an upside-down seesaw. So as you apply a force at the calcaneus, making initial contact, then there is a rotation about that ankle joint. Now, when you take that, when you make that first step and make initial contact, why does the ankle not immediately fall flat on the ground? How does it remain neutral? And the reason is, we have muscles that also serve to stabilize the joint. And I'm sure you're all aware of this, but our tibialis anterior, EHL, and EDL, they contract eccentrically to control ankle and provide ankle dorsiflexion and control that plantar flexion as we make initial contact. So the functions of the stance phase limb serve to provide shock absorption, as well as assist with forward progression. This is how we roll over our heel, our ankle, and our toe rocker functions. It maintains joint stability and prevents our leg from buckling, as well as maintains balance. So our foot provides this area where we can, as long as our center of mass, center of gravity is over that foot, we're balanced. It also controls the pelvis, assists with contralateral limb clearance and foot placement. Now, the first event is initial contact. As you see here, that ground reaction force projects up posterior to ankle, providing a plantar flexor movement, so your ankle wants a plantar flex. It's in front of the knee initially and in front of the hip, so your knee wants to extend and your hip wants to flex, I mean your flex initially. And you can imagine as you take that initial step, make initial contact, if you let your muscles loose, you'll see that sort of happening. Your foot will want to go forward flat, and you'll want to sort of, you know, you'll sort of bend forward at the hip as well. What muscles are activated at this event? At this event, your ankle dorsiflexes primarily, blocks your hamstrings and quads and hip extensors to provide some shock absorption. The loading phase is when your foot goes flat, you're still in double support, and this is when there is deceleration of ankle plantar flexion, so you're still controlling that. And then you progress forward onto your heel rocker. Here the ground reaction force is posterior to the ankle still, so it's providing that plantar flexor moment, but it's also now posterior to the knee and anterior to the hip, so this is where your hip and your knee will flex as well. So what's working here are your ankle dorsiflexors still and your knee extensors and hip extensors. What happens if you do have weakness of the ankle dorsiflexors? You'll end up with that foot slap, which is what you'll hear down the hallway as your patient walks to the examining room. Now in mid-stance, your foot's flat on the ground, and this is where your ankle rocker is working, and that's helping you forward progress over that foot. Your ground reaction force is now anterior to the ankle, so it's actually dorsiflexing the ankle at this point, and it's posterior to the knee and anterior to the hips, so your knees and hips are still wanting to go into flexion. So what's working here is actually your ankle plantar flexors are working to control that dorsiflexion, because if you have excessive dorsiflexion in stance phase, what will happen, your knee will follow, it will flex, and you end up with what we call a drop-off gait. So every time you take a step, your knee will buckle slightly, and you'll see somebody sort of bob up and down as you see them walking. Now terminal stance, this is where you go into single-limb support. You're progressing over your forefoot rocker here. The ground reaction force, as you see, is anterior to the ankle, still providing a dorsiflexor moment there. It's in front of the knee and posterior to the hip, so it's providing extensor moments in this. This is where your ankle plantar flexors are starting to fire as well, and as you have weakness here, you start to get impaired push-off. And finally, we have pre-swing here. You're just about to lift that stance limb off the ground. And here again, you're progressing over your toes, so it's your toe rocker, and your ground reaction force is anterior to the ankle, posterior to your knee and hip. And again, your ankle plantar flexors here are providing push-off. The other muscle to keep in mind here is your rectus femoris. In addition, your hip flexors are assisting with the initiation of hip flexion as you're about to go into swing. So again, if you have weakness of your ankle plantar flexors in this phase, you'll end up with an impaired push-off, which we see commonly in our patients. Function of the swing phase is something we're more easily able to wrap our heads around when we see somebody walking, because what are we looking at? We're looking at foot clearance, so you can see clearly, is the foot clearing the ground or are they dragging their toes? Are they scuffing their heels as they walk? And what this requires is concentric contractions of the hip flexors and the ankle dorsiflexors. In addition to this, the swing phase limb is also you're advancing that limb. So not only do you need hip flexion, but you also need your knee to extend, and that allows you to take a step forward. Otherwise, we just sort of walk in place if our hips are just flexing. In addition, we are preparing for initial contact, so that landing. I'm not going to go over too much. We're just going to fly through these because I want to show you a video as well. But the main muscles that are active are clearly your hip flexors, your ankle dorsiflexors. Now my question to you guys is, what's flexing the knee then? It's sort of a trick question, and you guys are free to shout out the answer. What is your knee flexor in swing phase? Now think about this as you're thinking about this question. Have you ever seen a transfemoral amputee walk with a prosthesis? How is their knee flex in swing phase? What was that? Inertia, exactly. If you bend your hip, your knee will naturally flex via the effects of inertia and gravity acting on that distal limb. Clearly, as you have weakness of the ankle dorsiflexors, where you have your drop foot, foot drop. Same thing with mid-swing. Terminal swing, things slightly change as your ankle dorsiflexors remain active, but you also get a little bit of eccentric hamstring activity. This is just sort of to slow down your knee extension. Otherwise, again, if you go back to the example of a transfemoral amputee, if they walk very fast, you'll notice they just sort of whip their leg out forward in front of them. So the hamstrings sort of act as little brakes here as well, and also provide a little hip and knee stability in preparation for initial contact again. Here I'll show you a video of a patient. She has sciatic neuropathy. After having two total hip replacements done, she comes complaining of falls as well as lateral hip and knee pain. I can play that video again for you guys if you want to. So what do you guys notice going on? Feel free to shout out. She has a valgus deformity at the knee. And she has a valgus deformity at the knee. What else? She has a Trendelberg. Good. What else? Does she have any issues with clearance? Yes. What's impairing her clearance? Here I'll play it again. Yes, she has a foot drop as well. Very good. You picked up a lot of things with her. Here I'll do a freeze frame. Clearly you can see she has, if you look at the first picture, this is her pathologic side, that's her left limb. You notice how it's a little bit more plantarflexed in mid-swing compared to the other side. You notice how there's a little less clearance there as well. And as she goes into terminal swing, what you notice is where is she making initial contact? She's about to make initial contact at the forefoot, versus on her normal side at the heel. However, in stance phase, what you notice is not in addition to having her knee go into a little valgus, hips and knees, you notice on the pathologic left side, her knee is also slightly more flexed, in addition to her ankle being more dorsiflexed. And this is sort of that drop-off gait pattern that I was describing to you. Now, when you mention Trendelenburg gait pattern, that's exactly, what about the frontal plane? And you can see, how do we fix that? In this case, you just have to give her a cane on the opposite side. Oh, perfect. Perfect timing. As you know, normal pelvic drop is approximately 5 degrees. And this is due to the weight of the contralateral limb, pelvis and body, creating an abductor movement. And then the gluteus medius provides a counteracting abductor movement. And you have ipsilolaline as a compensation. All right. All you. Oh, thank you. Yeah, that was perfect. Good afternoon to everyone. I'm sorry, they had a little technical difficulty, so we were trying to figure it out. I think they're just loading the file now. Okay. I don't know. Those headlights are bothering me. Yeah, I can't see anything, so that's okay. So thank you, Dan. Thank you for that. We're going to now move into the idea of how do we look at pathological gait? And then how do we, in the end, prescribe an orthotic device? So do I advance from here? You advance from there? Yeah, sure. There is a little clicker here. That's working. So disclosures, none relevant. I hope we're going to attain to this educational objectives. We're going to be looking at human gait. We're going to be using video as a way to identify the timing of gait problems, and then hopefully figure out appropriate orthotic interventions. And then we'll do and select and prescribe orthotic devices to address the gait dysfunctions, and then look at patients and see did we make progress or not. So unfortunately, I did not see what Dan presented, but thank you for that, Dan. But I have a question. Anybody knows what normal walking velocity is? Hands up. Anybody? There's a good hand. Go ahead. Three miles an hour. Very good. So three miles is a good way to measure that. Yeah, give him another pat on the shoulder because there are a hundred people sitting here and nobody seems to know. What do you do for a living? You are in rehab. Is that right? Just to let you know, just to let you know that walking is a very important marker, both for health and for function. And so not everybody can walk, but those that can do. So how do you measure walking velocity in your office? You walk your patients for a mile? 10-meter walk test. Very good. And what's the result of a 10-meter walk test? No, what's the result? What do you expect to get from that? Velocity of walking. Very good. And so if you walk a patient for 10 meters, you can judge their walking velocity. Very good. So that's what you want. So an alternative is to look at a patient and say, they walk about 80 meters per minute or 1.3 meters per second. And going back to your point of the three miles per hour, what about cadence? Anybody knows what cadence means? Any musicians in the audience? There's one. What's cadence? Steps for minutes and not in music, but yes, that's what we're looking for. And so in normal adults, we take about 90 to 120 steps per minute. What I'm trying to do is give you tools for you to measure your patient's performance in your office. You don't need anything fancy. You could do it there. So all you need is a measuring tape and a watch and of course a patient. So you need those three things. Did I see a hand? No. Okay. So there are implications for walking velocity. And so that's why I like to start with walking velocity. If you walk at 0.2 meters per second, you're essentially a household ambulator. It means you cannot go out of your house because if you're walking so slow, by the time you cross the street, you know, three lights went by and you got run over by a truck or a car. Now, 0.4 to 0.6 meters per second means you're a limited community ambulator. 0.8 to 99, you are a community ambulator and then anything over one meter per second, you're an unrestricted ambulator. Okay. You saw from Dan's presentation, I'm going to assume he talked about range of motion of the different joints. We measure this in the gait laboratory and we call that kinematics. So it's just the motion in three dimensions of the joints. Up is flexion. Down is extension. Normal range of the hip, you could see it determined there. The same for the knee. The same for the ankle. But what makes it really interesting is the complexity of this superimposition. You have to have coordinated motion of your hip, your knee, and your ankle to walk well. Now, you can lose two out of three. You can have a bum ankle and still walk around pretty well. If you have a bum knee, you can still get around pretty well. But if you have a bum knee and a bum ankle, that's trouble. You're not going to be able to walk very well. And so the way to think is that you have essentially three important components and you can sacrifice one but not sacrifice all three or two. So I'm going to ask a quick question here that's important for you all to know. What's the normal range of hip motion for walking? Normal range of hip motion for walking. Yes, please. 30 degrees extension. 30 degrees extension. And 40 for flexion. Maybe a little too much but not too far off. So you would need a little bit less extension. In fact, most of us, because we attend lectures and sit most of the day, we end up with less hip extension. But you want to have about 10 degrees of extension and about 30 degrees of flexion. What about the knee? Anybody else can help? What's the required motion at the knee for walking? You want to give it a try? 60 to 70 degrees. 60 to 70 degrees. 60 to 70 and where? Flexion. Flexion, 60 to 70. And extension? Zero degrees. Zero degrees. Very good. So from zero to about 60 degrees. That's what you need for normal. And we're talking about walking on a flat surface. If you walk on a different terrain, sand, for example, Puerto Rico. Is that where you're coming from? Yeah, Puerto Rico. Likely you would need more hip and knee flexion. What about the ankle? How much motion you need at the ankle? You want to help us? 40 degrees of dorsiflexion. 60, 70 of plantar flexion. Ooh, that's a lot of range. Repeat that. 20 dorsiflexion. And about 20 of plantar flexion. If you get around that, you're good. Okay? If you have to have your ankle fused, you know, the orthopod comes and says, you have severe arthritis on your ankle. We're going to have to fuse your ankle. Where would you like your ankle fused? Neutral. Very good. Why neutral? Because you don't need that much in either direction. Actually, if you could just have two degrees of plantar flexion, be good. But those orthopods can't do that. So neutral is good enough. Very good. So I'll just outline there the amount of motion. Very good. So this is normal walking. You saw that the reason I'm showing this is because you're gonna see a lot of this kind of walking videos and I wanna be sure that you get accustomed to that. The red line that comes up from the floor is the ground reaction. We can project that on top of the patient and so that's what you're seeing. Muscle activation. I'm gonna very briefly talk about muscle activation because it's very easy. You just think about motion and you understand what muscles are doing. So if your knee is in flexion and you need to stabilize your knee, what muscles are gonna be active? Yeah, your knee extensor is perfect. So you use your quadriceps to stabilize your ankle. Are there any other muscles that you use to stabilize your knee when you're in stance phase? Yeah, what else? Your gastro, your calf is very important. It's a very important muscle to stabilize your knee. Very good. So if you think about it, is essentially controlling gravitational forces. Muscles do that. And don't try to learn the muscles based on, ooh, maybe it's this time and that time and the other time. It's very complex to do it that. Think about it from the point of view of the biomechanical function. Okay, enough of that. We're gonna talk a little bit about braces and essentially what are the biomechanical features of braces. So I like to think in episodes, my brain has constraints and I have like two neurons and they only work sometimes. And so I like to think in things that I can assemble. And so this is a way to assemble what braces do. Function of braces. They control a deforming force. They correct a deformity. They accommodate a deformity. Sometimes you can't correct it. And then finally they can provide assistance to motion. Those are the basic features of orthotic devices for lower limb. You could apply this for the upper limb, but since we're focusing on walking, I'm gonna talk about that. Any other, anybody else comes with any different sense of what you can use a brace for? Have you come up with any other ideas? Sure. What about controlling tone? Controlling tone, they're terrible at controlling tone. Braces don't work at controlling tone. You can control motion that then controls the tone, but they're not good at controlling tone. In pediatrics, there was this whole idea in the past that you could put tone reducing braces or tone controlling braces. Nobody could prove that they really work in doing that. But good point, thank you. Any other concepts? Yes. Compensate for weakness. Compensate for weakness. Well, they assist motion or they accommodate a deformity or they correct the deformity or they control the deforming force. So that's what they do. Okay, yes. Pain control. Yeah, I mean, you're not really controlling pain. You're controlling the forces around the pain. So yeah, in the end, it can happen. Okay. The other way to think about this is they control falling. You know, if I give you a good brace, you won't fall, that's a good outcome. Oh, also that restricts motion. Restrict motion, very good. So you're correct. I usually think about that from the point of view of controlling a deforming force, but good, yes. And I think that if you think about motion control, then it could focus very nicely with the pain control that was brought up as an idea. So yeah, good. I'll add that one to my list. Thank you. So this is a paper that we published some years ago. And the reason I'm showing it to you is just to prove the point that braces can improve walking. And so you can look it up. It's a very nice brace. We compare patients walking with and without their brace during the same session. And so it was pretty straightforward. We could prove the improvement. And, you know, there was a significant improvement in walking velocity. Okay. So how do I think about an orthotic prescription? When I'm putting together an orthoses, what do I think about? I usually like to think about what's the problem. And, you know, I use the what, where, when, and why. Everybody's clear on that? Yeah. What's the what question? Anybody wants to help me? What joints? What joints? That may be one way to do it. Or maybe we could say, what is the problem? Correct? But yeah. So where? The joint, where in the joint. That may be a good way. Or the other is where in the gait cycle. Is that right? Because a brace that controls a foot drop, is the foot drop a problem in swing or in stance? So where in the gait cycle may be important. When? Goes back to the idea of the gait cycle could be used then. And then why? Is it because there's weakness? Because there's pain? Because there's instability? That's going to change the approach that you're going to take to the brace. How many people here have written a prescription for a brace? Hands showing? Very good. How many people have written a prescription for a brace following this methodology? Good. Very good. A couple of you. Very good. Oh, I was going to just point to the idea of the availability of the device to do what you want. And then of course, to control the problem. And I like to think about nomenclature. And the reason I use this is because I want you to think about a brace prescription, not different in the way you write a prescription for medications. How many people here write one AFO? No, one right AFO. You laugh. I have proof of people that have written one AFO. I have proof in writing. I can show you that. I won't embarrass anybody, but as Tom Watanabe told me last night, don't throw me under the bus. I will not do that. Okay? So when you write a prescription for a brace, I want you to be as detailed as you can. Because you don't write for a prescription to the pharmacy, one anti-seizure medication. Who writes medication prescriptions like that? Your pharmacist won't take them. But the orthotist would. So be kind to the orthotist. Give them as much guidance as you can. Now, when you're so detailed, and sometimes you can be very detailed, orthotist will hate you. But that's okay. I'll take the hate. No worries. Anytime. So I use this as a, yes? If you don't have an idea, but you want something that you want him to control, can you give him the... So the question was, if you have no idea exactly about what you want to do or how to do it, can you give them an idea and sense, you know, I would like to do this, tell me how to do, by all means. By all means. You know, I've called a pharmacist and say, I have this patient with 10 different drugs. Is there a drug to drug interaction? I don't need to know that. He knows that very well. And he'll tell me there is a drug to drug interaction. Maybe you want to consider changing the medication or the dose. Same here. You don't need to know the names of every little joint that it's made in this world. There are too many. But you could say, I want a brace that controls X or Y, and he should be able, or she should be able to produce that. I use this as a way to kind of focus you on how to look at a problem. It's a very simplistic approach. What you're seeing is the different components of the body on the left side, and then the different components of the gait cycle. You did talk about swing and stances, all right? Oh, thank you. Great. I expected that, but I wanted to be sure. So you just want to be sure that you are able to do that and look at individual, and this lets you check quickly, where is the problem? When is it happening? Is it at the hip, at the knee, at the ankle? Is it at the trunk and the head? And when in the gait cycle is occurring. So I usually like to think a brace is effective only if you can correctly prescribe it. And there is no one more particular about that than patients who have had polio. Polio patients are the most challenging brace users because they know exactly how the brace should work, and they will tell you. And so they are very challenging. A patient who has never worn a brace has a stroke and you give them some brace, doesn't have to be too perfect because they don't know any different, and you get away with that. But in patients who are very relying on their brace, mechanics will know. You need to identify the desired brace function. This is going back to you. You ask, you know, can I tell? You can tell the orthotist, this is the function I want, and that would be terrific. And then you have to communicate in the way, same way as you do with a pharmacist. So, you know, this is a molded ankle for orthoses. Do they look the same? No, but they all have the same name. So you have to refine that information and talk about what it is that you're looking. Remember, all braces work under the principles of three points of pressure. It's very simple to think about that, but sometimes it's complicated to understand where the three points of pressure are. But all braces will work under that system. So here you have a double ankle foot orthosis, double upright ankle foot orthosis. That happens to have an inversion control. And what I've done is put arrows around it just to show you where the three points of pressure are. Okay? Now, you may not think about the top of the shoe being as one point of pressure, because you don't consider that part of the brace. But remember, the footwear is an integral part of an ankle foot orthosis. So always think that way. If you think about a brace made out of plastic, it has the same three points. The points didn't change, it's just the construction material that you use. There are a bunch of joints, and articulating braces are very appealing. Everybody wants an articulated brace. But important to know, and I'm going back to your spastic patient, you want to be sure that they have the range before you give them a brace that has a joint. Because otherwise, you're going to have a fight, a brace that doesn't move when the joint, I'm sorry, a brace that wants to move when an ankle joint doesn't move. It increases cost, it increases bulk, it increases maintenance. And then, no doubt, articulated braces will give you a more natural walking. Anybody wants to tell me why an articulated brace at the ankle will give you more natural walking? Yes. Because you're not in a ski boot. Because you're not in a ski boot. Very good example. Now, a ski boot is usually in dorsiflexion. So a brace doesn't have to be in dorsiflexion, but you're very right, it allows you for motion, and so that's important. And then, just remember that braces that have joints can have an assistance, so you could put a dorsiflexion assistance. Please, do not try to put plantar flexion assistance. Little springs can't produce the force that you need. You need to have about a two horsepower motor in order to produce that kind of force. And just be aware, braces that are articulated are very nice because they can change with the needs of the patient. But be aware, patients can sometimes have a brace that changes without them wanting the brace to change. Now, you don't always need to have a joint. You could put a brace made out of plastic. And what you could do is control the amount of movement by the trim lines. Trim lines refers to how far back the plastic is cut out. Is that clear? Do you understand that concept? I wanna see a few more heads nod or not. Yeah, okay. So the reason for this is because if you have flexibility, you essentially can have movement. You can flex the plastic into dorsi or plantar flexion if it's very flexible, or you can make it really, really very stiff as if it had no joints, as if it was locked. Now, it's nice because you could take a brace, make it really very stiff, and then cut it back and make it very flexible. Just remember, cut it back, just remember, carpenter's rule falls. You can only cut once, so measure twice. Make your decisions. You can't make the plastic grow back. I'll briefly mention knee-ankle foot orthosis. We're not gonna spend time on that today. But what you see here are knee-ankle foot orthosis of different styles with many joints. They also have three points of pressure. It is not different than an AFO. You're just putting it in a different position. Knee joints come in a variety of styles, single-axis, offset, polycentric, locks, bail locks, dial locks, and there are a bunch of other nuanced locks. This shows you some of those that produce stance control. Yes? Can you just go back to that three points of pressure associated with AFO? You've got three points of pressure across the ankle and three points of pressure across the knee. Usually, you don't need to have three points of pressure in each joint. You could have them depending on what your function is. The question is, where are the three points of pressure in a KAFO? You have three points of pressure at the knee and three points of pressure at the ankle. You could do that, but you don't have to, okay? There are a variety of stance control braces from mechanical to microprocessor control. So you have the whole array of devices. So this is where I wanted to get. These are cases, and that's what I want to get to. But before I do that, up to this point, any questions? Is there a question? Make the question. Yes, trim lines. Yes, I specified that. We'll get to that in just a second. So you do specify that. I want a brace, an ankle foot orthosis made out of plastic, and you stipulate the resistance of the brace as well as the position of the ankle brace, okay? And you would stipulate that by saying maximum, moderate, medium, minimum, or even a posterior leaf spring if you wanted to do that. Other questions? So important question. Have you learned one thing so far? One. Okay, yeah, you said yes, good. Oh, he learned two, that's good. That's very good. Okay, so, oops, sorry, I jumped the case. So this is a 44-year-old woman. She has a history of a right hemiparesis after a stroke, and she's 19 months prior to presenting for evaluation. She has difficulty walking with an AFO that was recently prescribed by her physician. Some physiatrists that did not come to this course today and provided the brace because she had some deficits, a foot drop related to her stroke. So that was the reason for the brace. She says that, you know, I was able to walk before, and am I able to walk now, but I'm having new right knee pain. Since I started using this brace, I have knee pain, and I feel more unstable when I walk, and I have had a few falls and some back pain. So her complaint is not the fact that she didn't walk well before. She knew that she was not walking well, but she feels something is not right with this brace. And she has hypertension, and so her doctor who prescribed the brace said, you know, I don't know what's wrong with this brace. Why don't you go see that nut guy that knows about braces? And so she came to see me. I'll just point that she has limited ankle dorsiflexion, minus 10 degrees. How much dorsiflexion you needed, we said, when you walk? 20, and so she's at minus 10. So she's negative 30 of where she needs to be. She has zero strength for ankle dorsiflexion. She has three over five for plantar flexion. And you can see that she has no more inversion, eversion, weak ankle dorsi, I'm sorry, weak ankle inversion and eversion. Weakness at the knee, three over five, and weakness at the hip, four over five. You will notice that her knee hyperextends 10 degrees. Okay? The rest of the exam is pretty good. She has impaired motor control for the ankle, the knee and the hip. She has clonus at the ankle, clonus at the ankle, spasticity, tone, and she does not have any clonus at the knee, and she has impaired light touch sensation, but she has normal proprioception. So this is her, and do you think we can make the video play because now I'm not sure. It should have played automatically, but I don't see it play. So you might need to drag the video and make it play. There you go, lovely, thank you, appreciate that. But actually you see her here walking with her brace, which was prescribed by her physician. And we're gonna let her walk a few times so that you could see her. So what's the problem? If anybody sees a particular problem, yes, sir. Okay, okay, so she has retrovatum, very good. She's banging the heel, okay. I've never heard that as a term for a gait deviation, but I'll take it. Anybody else? Hyper-extends the knee, very good. Hyper-extension, retrovatum, very good. Oh, valgus, do you see valgus there? Yeah, okay, I'll take it. Anybody else? Circumduction, okay. So is circumduction a primary gait deviation or a compensatory gait deviation? Compensatory, yeah, don't treat circumduction until you've treated the problem, okay? Because you'll go nuts. And so what's the problem? Why is she complaining of a sense of instability? Why is she complaining of back and knee pain? Why is she falling? You have the answers, tell me. Good. So, it's interesting. She goes into knee hyperextension, but destabilizes her knee. So, not quite, but it's a good observation. You got most of the elements is the timing, and we'll come back to the timing. I'm going to skip you for a second so that I get a few other people, because you two have been very active, and I want to be sure that I get the people in the back. They usually have, you know, are half asleep, so we'll see. Tell us anything else that you see. Don't get nervous. If you don't know, you could just pass it to the guy next door. Don't know, so pass it to this guy. He seems to know. Yeah, what else do you see? Oh, sure, sure, sure, sure. I'm trying to repeat the answers, but go ahead. I'm not entirely sure what else to add. Okay. He's not entirely sure. Anybody else is entirely sure? Yes, there is a gentleman back here. So, it's difficult to see the trim line, but it looks like the anterior trim line is posterior to the malleolus. Either way, it looks like she's not getting a proper support. So, she might, it looks like she's, it's difficult to tell with the shoes, but it looks like she actually has inherent ankle instability, which is not being supported by the brace. Okay. So, do me a favor. If you don't mind, go sit in the front and look at the video. No, no, do that because there is no trim lines. I want you to be able to see well. Okay. So, there is no trim lines. This is not a plastic brace. It's an ankle foot orthosis made out of metal. And so, there are no trim lines here. You could talk about the alignment of the ankle. That I would take from you, but not, you have a point. Yes. Hold on. I need to get the microphone close to you because if not, they, you know, don't like it. So, she's not flexing the knee in swing. Good. So, ground clearance is a big problem, and I don't know if the brace is too heavy. Okay. If that's part of the problem, why she can't lift the knee. Okay. And it's very plantar flexed. And very plantar flexed. So. Okay. So, we're going to look at that. That's all good observations. Now, remember, the fact that she cannot flex the knee. When does that supposed to happen? Swing. In swing phase. So, no knee flexion is a swing problem. Does she have a swing problem? Does she have instability because of swing phase? No. Because she's actually clearing the leg. Either because she's circumducting, as it was suggested, or because she's hip hiking, or because she's throwing the leg, as it was suggested over there. Whatever it is, she's not dragging her foot. So, she does not have a limb clearance problem. What does she have? Yes. There's a hand on that side. What do you mean it's hard to tell in the video? This is a perfect video. You know how many hours I spent collecting this video? Good. So, the point that was made is it's hard to see on the video, but if you could actually measure the moment or the torques around the knee, if the knee was pushed forward, she would collapse. And why would she collapse? Because she has 3 over 5 strength in her knee. You remember that? And I pointed to that on purpose. I wanted you to be aware. So, this lady had a foot drop. You remember? That was why she went to the doctor. And the doctor said, I have a solution for you. I'm going to give you a brace. And gave her a brace that controls foot drop. Controls foot drop. So, I'm going to look here for an angel. What kind of brace controls foot drop? An AFO. Excellent. An ankle foot orthosis. Can you be a little bit more specific? Give us a hand here. A dorsiflexion assisting AFO. Okay. A dorsiflexion assisting AFO. Very good. So, that could be one solution. Very good. Any other solutions? You could stop the foot from going into plantar flexion. So, you could put a brace that has a plantar flexion stop. Very good. So, you could stop the brace at neutral. Very good. She said it right. You see? She knew it. It was there. So, what you could do is do that. Now, watch the red line on this lady when she comes back. It's good to have her on video. She doesn't get tired. You see? If you pay attention when she turns around. Turn around. Come on. And do you think you could stop the video? Is that something you could do? Or am I asking too much? There. You see the line? The line is way in front of the knee. Okay? Way in front of the knee. Why is the line in front of the knee? What could we do to resolve that line in front of the knee? Change the position of the ankle. Very good. In which direction? So, he wants to put more dorsiflexion. How many hands are with him? Show of hands. Come on. One, two, three. You have about ten followers. How many people would leave the ankle where it is? How many hands? How many people would put the ankle into more plantar flexion? There's one, two. How many people have no idea of what we're talking about? The rest of you. Okay. So, yeah. The problem is that they put this brace and they locked the brace in a position that limits the motion into dorsiflexion. So she cannot dorsiflex the ankle. And as a result of that, she is like this. So, what can we do to fix it? Hold your answers. Hold your answers. Not quite yet. Can we move to the next? Oh, I have the movement here. So, we talked about all of this, so I'm going to move here. So, here she is after I modified her brace. And let's see if it plays. No, it didn't play. Do you think you could jiggle your machine? Maybe you make it do something? It's not? Sure, I'll go back to the last one. Yeah, that one we do. We need the next one. Otherwise, we're just watching the same video. There you go. Can you think if you can make it play? No. Okay. So, this is what happens when you come to the academy and they can't use your computer. It doesn't work. Anyway, so, what I want you to, well, let's look at it here. So, what I did is I took three single frames and I did that on purpose because I knew the academy was going to have trouble with my computer. And I said, I'm going to fix this. The past president of the academy can't get the computer going. We'll be sure that we address it. So, on the left side of the screen, you see her without a brace during single limb support. Single limb support, also known as mid stance. Okay? And you see that red line. And that red line is in front of the knee. It's in front of the knee because she has that significant equinos that I discovered when she was being examined. Probably has a little bit of tone, too. So, in the second image, what you see is the brace that was given to her. And the intent of the doctor was, you have a dropped foot. We're going to address that. By the way, you have a little bit of knee hyperextension. We're going to control that. But what you see is that because the brace forces her to not be able to dorsiflex at the ankle and is pushing forward, she ends up feeling unsteady. In fact, the red line is closer to the knee. You could see that. So, it's less of a force. So, what I did is I did something very simple. I build the heel of her shoe. Did not change any settings in the brace. I could have done that, but then I would have no case to show you and I wanted to show you the case. So, we build the heel. I put a little bit more of a quarter of an inch heel under the shoe. And by doing that, what you see is the line moved. Can you appreciate that? I mean, I tried to mark it. I put little diamonds and everything. So, that's great. I think I did a good job. Probably could do just a tiny bit more, but I have to be careful. If I do much more, what would happen? Knee will buckle. Yes. Knee will buckle. So, you still want to have some hyperextension, but not so much as we had in the beginning. Not restricting her dorsiflexion as we have in the center, but pushing the tibia forward. That's the intent. Yes, you have a question. Hold on. I have to get with a microphone because the lady doesn't like me. I'm missing the connection. So, when you add the heel, that makes more of a plantar flexion. Very good. It's a great, great point because it's hard to understand. You're putting a heel. Let me see your shoes. Oh, terrible shoes. Anybody here with a... No, no. They're beautiful shoes, but terrible for the demonstration. Oh, you have perfect shoes. Come on over. Thank you for that. If you're embarrassed, don't worry. It's okay. We're not going to make you be embarrassed. Can you walk a little bit for us? So, she has tall heels. She's a great walker in tall heels. She's doing that. Come back. But her tibia and her knee are not hyperextending. Is that right? She walks pretty well. She probably is using a lot of strength to keep herself walking well, but she does not hyperextend her knees. So, I'm going to ask you something that it's probably you can say no. Would you be willing to take your shoes off? Sure. Yeah? And walk without your shoes. Thank you. And the reason I want to do that... Don't laugh because I'm coming after you next. You'll see. Yeah. Great. And just walk. Does she look... I mean, she looks different because she lost height, whatever it is, but her walking is not hugely different. Her tibia rotates forward. Now, if she only wore high heels and she comes back to see us in 10 years, it will be a different story. But I'm sure she does not always wear high heels. So, I'm going to borrow your shoe. Is that okay? Can I borrow your shoe? So, for those of you that didn't see, you could see this is a tall heel. And this is very frequently seen in older women who wear very stylish and wore high heels for long periods of time. They come back and they said, ooh, I feel I cannot walk. You check their ankle range of motion. They have limitation in ankle range of motion. Thank you very much. I really appreciate your help. That was wonderful. I mean, wonderful that you were able to do all of that for us. So, where's the guy who was laughing? Oh, I'm going to get him. I'm going to get him for laughing. So, we're going to ask you to do something for us. You're going to walk for us if you'd be kind enough. Sure. If you had never been to one of my lectures, everybody gets embarrassed. So, there are no excuses here. Just walk. Very good. Very good. Very good. Now, turn around and come back. Good. So, we're going to ask him to do something that is slightly different. I'm not going to ask him to wear the shoes of the lady. But I'm going to ask you to walk on your tippy toes. So, first of all, he has weakness on his left ankle. So, if you didn't know that, I'm giving you that. And second is, you know, we just asked him to walk on his tippy toes. And he walks now with a stiff knee. You know, there's no connection between one and the other. But we force him to change his walking pattern. And he shows that there is compensation. Because now, he has to figure out that his foot is in a different position. So, thank you for that. You did a great job. So, I'm looking for hands. If there are any hands. Because sometimes I miss them. So, you could see that. Dan, how are we doing with time? How many? Two minutes? And I'm done? Oh, Jesus Christ. Hurry up. I have 15 cases and we've only done one. So, this is not good. So, what I wanted to do was to just show truncal posture. You remember she had complaints of back pain? Look what happens when she's not wearing a shoe. Now, what phase of the gait cycle is she in? No, not mid-stance. That can't be mid-stance. Both feet are on the ground. Is that right? You see that? So, she's actually in terminal stance. Because the other foot is down on the ground. Yeah? You see the distance between one foot and the other? Very short step with no shoes. You could see that with the brace, in order to take a longer step, she has to hyperextend her knee. And look at her trunk. You see her trunk leaning forward? Look at the last picture. My beautifully corrected brace. What happened to her trunk? Much straighter. And she still can take a nice long step. Okay? So, you have heard the song that says that your ankle is connected to your shin bone and your shin bone is connected. It's true. We are all connected. So, you better be sure you're fixing all the parts. And just you can see here the trunk tilt. And what would be the ideal prescription for this lady? Would you choose a plastic brace? Would you choose a metal brace? Would you choose maybe a carbon graphite brace? Well, she already has a metal brace. Stick with that. You know? What the heck? We're not going to waste it. Someone paid for it already. It's articulated, non-articulated, limited motion. We'll put limited motion on it. We could put assistance if we want it. If it was going to be made out of plastic, we go back here. You could make it rigid, moderate rigidity, or flexible. You could make it molded. You could customize the brace or make it off the shelf. You could implement shoe corrections. You could place brace corrections. So, lots of choices for you. The important piece is think biomechanically. Think biomechanically. What do I need to do? Control the knee, but not too much because she doesn't have enough strength. Control the ankle. Oh, she has a limitation in the ankle. So, I can't put the brace in neutral when her ankle doesn't get to neutral. So, I leave the ankle in a little bit of plantar flexion, build the heel. And I have not missed your point about the heel. But I'll come back to you because I know you still have the question in your head. I can hear it. So, that gives you a sense of what the brace would be. So, as I said, I have 22 cases. So, I want to get to the... Yeah, hold on for a second. I wanted to get here. So, I use this as a guide. It's just essentially a place where you can have all the elements for a brace. Anytime you want it, just tell me. I'll give it to you. Of course, this was a perfect paper document. Now, it's an EMR. And so, EMRs don't have all of this. But it's a good reminder of how to do a prescription. And that's all I want you to do. I'll come to your question. I did not forget your question. Give me a second. Let me close for the rest of the people. So, questions at this point. We went really on a really fast flight. I hope that this has been helpful to you. Now, you have a question. Go ahead. Ask your question. Why not a KAFO with the retro bottom and the quadriceps weakness at 3.5? Good. So, the question was, why not a KAFO for a patient who has a retro bottom and weakness of her knee? Because she can walk without it. She will abandon it. It's too much. It's an overkill. You don't need that. Okay? Yes? How directly involved do you get on modifying an orthosis? Oh, I get very involved. I mean, I have tools. I don't wear a stethoscope. I have all sorts of tools in a drawer. I don't carry them around. And yeah, I do. I do. And I have a grinding machine. I grind plastic. I have a heat gun. I heat and push. So, I do all of those things. Yeah, I'm a strange physiatrist. Any other questions? Yes, please. Why not a KAFO for a 4-year-old who's got a walk like this for 30 years? Yeah, she will not. She will not because, you know, the idea is to control, not necessary to completely eliminate. Can I fix that? You can, by all means. And you have a brace that you can adjust. So, that's lovely. So, you could do that. So, this is about bracing. You know, if you come to the next session, we'll talk about botulinum toxin. We'll get that done there. Okay? Or surgery. Why not? Any other questions? Okay. Time is up. So, I have to give you up. I hope this was useful. And thank you very much for joining us today. Thank you, Dan.

biomechanics

human gait

lower limb orthotics

neurorehabilitation

gait cycle

stance phase

swing phase

orthotic devices

gait abnormalities

foot drop