0:00 Next up is injury prevention and rehab. Now I will use an example to sort of build a picture here. Injury prevention is one aspect which can be seen as prehabilitation, or after you have had an injury you have to be
0:45 rehabilitated which basically means you have to undergo therapy physical, physiological, occupational to recover the functions or the ability to perform the activities that you were able to perform or need to perform to sustain not just sustain life functions but to thrive and live a good life. So the rehab could be driven by injuries in sport. So if I was to take ACL injury as an example then I can understand the characteristics of a particular joint movement and from that I can understand whether a person has a propensity for ACL injury or not
1:32 by studying their dynamic movements and seeing if they have a propensity for collapsing the knee towards the central line of the body which is to say the knee abduction movement. We looked at this that abduction can cause ACL tears in the knee or ACL injury and after that it requires surgical intervention, and long physiotherapy, and recovery time before the person can return to the sport or just to normal walking because you require you have lost a lot of stability in that knee because of the loss of that ligament. So on the prevention side if I can study the
2:20 particular characteristics of that individual's movements that is one way I can identify the injury propensity so I can make them do these standardized tests where if the knees collapse inwards I know you are more likely to get injured let's develop a training program that helps you improve your movement patterns and enhance your overall performance and reduce injury propensity at the same time. On the rehab side after the injury has happened unfortunately after a surgical intervention you have to undergo the rehabilitation process where you perform movements
3:07 with gradual intensity and load and you recover your strength and your coordination for movement patterns over time and you are able to get back into normal workflow of activities of daily living or even sports. Now it might if you think about the human body as a system it is a system it is a musculoskeletal system it's not just the skeletal system or the muscular system again it's not just the muscular system or the neural system in isolation right it is the neuromuscular system as well which interacts with each other and actually produces the outcomes. For that to happen
3:54 we cannot just say or and this is rather the newer directions in which the research is going that the behavior that I study so in the case of ACL injuries I studied the person's propensity for the knees to collapse during a particular movement and just correcting that that might not be enough and this has been shown statistically that despite the interventions being performed at an early stage itself a lot of ACL injuries are not prevented. So then it makes sense to look at what are the other aspects of movements what are the other aspects that control the movements which brings in your neuromuscular system. So a lot of what you learned in motor learning comes in here right
4:48 if you recall there were different areas in the brain right you had so this is an MRI of a brain right and you had multiple cortexes the neocortex the motor control area the occipital lobe right there are multiple regions of the brain. So what part of the brain is responsible for a particular movement can be mapped with technologies like fMRI and even to some extent EEG and from that I can understand which part of the brain is active in people who have a high propensity for injury versus which part of the brain is active in people who are not in as injury prone and then the
5:33 research would be in how to target interventions to translate that learning from a different part of the brain back to the correct quote unquote correct part of the brain for a particular motor learning to be used for injury proof movements. So advancements in EEG and fMRI has specifically fueled some of the recent researches which help us understand say how injury rehab is progressing after a stroke after a concussion injury after during a rehabilitation process
6:19 say after an ACL reconstruction. So this there is there was basically a phase where people said hey the knee is down there and yes it is injured but it is also being controlled I am also able to control it with my brain so there's something interesting happening here let's study that. So this new connection was built and from there we can now look at causes of or origins of sort of neural misfires which are causing injury which might be causing injury. The other area of interest is robotized rehab. So typically in the past after a particular injury say a stroke the
7:12 therapist would perform a lot of these rehab tasks when the person does not have the arm strength or the wrist strength or the fine motor control skills. So the task would have to be manually performed by individuals and the interventionist or the clinician would typically assist in that task or try to provide resistance in that task. As you can imagine there would be variability in the characteristic of the intervention performed by one doctor or one clinician versus another. So to sort of standardize the treatments or to customize the treatment for an
7:59 individual a robotized rehab came in where a robot can provide the assistance or the resistance in a very calculated way and sort of understand your behavior over time and adjust to that as well. So these robotic interventions can help sort of standardize the entire treatment protocol and scale up or scale down according to the individual in a very precise way and also at the same time be able to record the performance. So you can imagine this is another source of data for understanding an individual's performance improvement over time or their progress in the
8:44 rehabilitation phase. Now all of this basically has increased the accessibility of rehab and the availability of all these and on the other hand, the availability of all these sensors in our daily devices has to some extent helped us understand our movement patterns better and prevent us from performing movements or from getting injured which is what's characterized under prehab. So if I have for example knee pain during a particular movement and I do some exercise and I do a video
9:34 recording or I use IMU sensors to sort of collect data on that which are commonly available I might be able to see some patterns in the movement itself which I can identify okay this is bad this is the reason you know I'm getting some knee pain so I need either a form correction postural correction or an external aid or something to move better and not get injured right. So the availability of sensors itself right and solutions with sensors has started to show that has started to provide that sort of reward that you can have these prehab instead
10:22 of requiring rehab later on after an injury. So we've talked about some of the sensors now force measurement is a very specific sort of a sensorized measurement but it is of critical importance it is a fundamental importance in sort of understanding the dynamics of human movement and building better solutions. So with that in mind there have been improvements in the way we have been measuring forces for anything from gait analysis to rehab devices and one of the areas that has seen significant improvement is force plates. Now force plates are devices which are laid on the floor. Usually, they're rigid and when you step on them they give you measurements
11:14 of force in all in one direction or all three directions X, Y, and Z, right? And they also tell you where is the center of pressure where if all of it was to be lumped where is that force vector acting on that surface. Now these tend to be quite expensive as you might imagine because they are high-precision instruments. But over the past years in fact over the past decade now we've had a significant increase in the quality of embedded force plates which can be embedded in the floor. So you can have what are called gait labs where people walk on a surface and when they step on it you identify the force movement patterns. So those force vectors might look something like these,
12:06 right? These are called butterfly diagrams of force patterns and as you can imagine if this person is running, right? And I want to be able to measure their force pattern and the center of pressure and how it moves as they move their foot right throughout the stance phase if you remember your lesson on gait analysis, right? So the center of pressure will move gradually from back to front right when this foot makes contact. So that is possible by using embedded force plates. Now one of the limitations there is that you can only measure one foot at a time.
12:52 right? So I have to do multiple rounds of the person walking on the force plate capture their kinematics and dynamics to get a better picture of that person over multiple movements. To sort of resolve that we already have treadmills where you can walk continuously or run continuously. So people have now instrumented the treadmills which is to say that they have embedded force plates underneath and with some intelligent computation they're able to identify the force patterns, the center of pressure, and its characteristics with pretty much with a very similar precision
13:39 and accuracy as embedded force plates okay. Of course, if I just do this all of these are still huge instruments which require a lot of investments and a lot of space and are constrained to usually lab or clinical environments. If I wanted to do force analysis of an individual in an ecologically relevant task. So if I was analyzing a soccer player for example and they're playing in a field I do not have a force plate that I can embed there and get the characteristics because well that is challenging task to do. So the other way to measure is you have what are called instrumented soles. So inside the sole of the shoe you have these in soles, right? And
14:32 you might be you might have seen online or at the mall maybe that there are in soles available that you can replace or put in your existing shoe for different sort of sorts of contours which claim that they correct you know orthotic problems like knee pain or ankle pain. So same way there can be an instrumented in soles with sensors in it, specifically for sensors and it can measure the forces now they may not they're usually not as precise or as accurate as these embedded force plates or even instrumented treadmills. But they can help you understand overall movement patterns which can be beneficial for some sort of diagnostics or even just understanding the
15:25 you know how the person is how the athlete is generating forces and give them advice on how to do it differently or design a training program to have them develop those movement patterns, right? Additionally, you can have instead of insoles you can also have portable force mats. Now I just said that you cannot embed force plates in the field, which is still true. But portable force mats are typically so one example where they used is golf, where the golf player might try to understand how the force is moving from their rear to the front feet while they're driving through
16:12 particular stroke, right? so these are sort of flexible mats similar and principle operating principle to be in soles. Then you can have and finally, you can have dynamics-driven models. So if I have IMUs embedded on all the segments and I know their center of mass characteristics and limb segment mass and inertia then I can predict the force that is being generated and from that, I can calculate the joint moments. Again, this is always an approximation. It is not very accurate
16:59 as compared to say embedded force plates or instrumented treadmills or even any of these other instruments which are directly measuring the force but in the absence of any data this can at least help you understand some of the characteristics. So that's more on the research side and this these are more on the advancement side where recent developments have helped proliferate this concept of measurement of forces for athletic movements or for clinical analysis and again sort of democratized the availability of these technologies to people. all the engineers stinkers out there who have been playing with 3d printing have come up with multiple devices over time and
17:50 one of the areas where people have applied this is developing personalized prosthesis, medical implants, tailored sports equipment, customized assistive devices, right? so you have multiple open source projects available online where you can 3d print a particle of prosthetic prosthesis prosthetic hand or even prosthetic leg which of course might not have all the all the characteristics desired but again it's about making the technologies accessible. so advancement in these fields have allowed us to develop very customized shoes and insoles for example
18:42 to the individual's measurements okay. one of the interesting advancements in recent years has been the use of 3d printed prosthesis for bone repair right? so after an injury for example a portion of the bone is to be replaced with a 3d printed scan and 3d printer architecture which is embedded and once covered up it basically resembles the original structure right? Something that was not possible with the existing manufacturing technologies and this has truly revolutionized the field of medical devices. So again while this example is for the skull which of course the bones
19:35 should not be moving there. such applications have also been done for some of the appendages, hands, and arms and research continues in this field to make biocompatible 3d printed parts which can either be internally embedded into the human tissue as well and perform the same function as the original body, organ or part. now virtual reality and augmented reality have caught up caught on a lot in the past few years. so of course from a from a technological perspective you can have immersive environments right and with some of the latest developments in computational
20:22 science and rendering technologies, you now have photorealistic rendering. just to say the the rendered environment is very hard to differentiate from an actual environment. of course it's there are limitations to that as well and human perception is very interesting and it's always able to differentiate it but at least visually it's it's getting as close to reality as possible. In fact, even our virtual reality headsets have now reached sort of the human limit eye limit of 20 by 20. vision and the manufacturers and technology developers are still pushing that
21:09 envelope and developing even higher resolution for for ridiculous levels of fidelity which will truly revolutionize our perception of the world right? now the thing is these are technologies not just for games or just for rendering environments but they can actually be used for sort of these trainings and interventions. so here is a a sports athlete who is doing a combat training in a virtual reality environment and as you can see as you can imagine the person can be in a very photorealistic environment right and can have these multiple senses. so virtual reality
22:00 is no longer restricted to just vision feedback. you can have you can interact with objects in that virtual space and get sort of haptic feedback or force feedback and that is what makes it a very compelling device to sort of deliver either any sort of training or perform interventions and therapies. so things that are not physically possible are possible in this in these virtual environments. I can do one can change the visual field however they want right? so you can test a person's agility for example for for some of the dynamics sports. on the other hand
22:49 if someone has undergone a particular injury and they're undergoing a rehabilitation therapy then some of these therapy is the the feedback can be driven can be given through a virtual environment right? and these environments can be gamified so the person has to do tasks to sort of engage with with the program which also captures the data performs analysis on it and can help can overall make the process of rehabilitation or any intervention more engaging and there is plenty of literature on this now which shows that the more you engage people in their rehab process the more
23:40 they are they're likely to return for rehab and continue or continue through the rehab phase until full integrating with their original functions. and last but not the least I'll just briefly talk about genomics. so genetic have been used to understand the relationship between genetics biomechanics performance injury propensity. so I'm not going to go into too much detail on this just that we can identify the response to you can identify an athlete's potential for example or how
24:32 they will respond to particular training or a personalized their injury prevention protocols or methods to based on statistical analysis on what has been effective across when a particular genetic characteristic is observed. and you know there's a lot to this to this field itself which is there's no way to do justice here. But just that there are advancements in genomics. So those of you who are interested in genetic engineering or and is or just gene therapy and understanding personalized medicine you can still be affiliated with the human movement science field. If that is
25:19 of interest to you because you can still correlate the fundamental characteristics of movement to the building blocks of the human body or any organism which is their genes. So with this, we conclude this particular video to summarize the developments and there have been developments in the fields of engineering and medical sciences like material sensors computational resources advancements in robotics on the medical side there have been imaging techniques advancements in genetics neuromuscular modeling all of which is towards the democratization and increased accessibility of these technologies and interventions and
26:10 rehab processes to the common public to both improve performance enhance abilities and enable possibilities. So we'll conclude this and I will see you in the next one thank you
