Exploring Cutting-Edge Prosthetic Technology and Interdisciplinary Approaches to Human Movement
At Humotech, we are deeply inspired by the personal stories of researchers and developers building solutions to advance human mobility. It’s their determination to create a more accessible and healthy world that gives us purpose in proliferating the world’s first platform dedicated to advancing wearable machine technology.
Today, we’re pleased to share with you a new format of exclusive interview with one of our longtime collaborators, Dr. Kota Takahashi, Associate Professor in the Department of Health and Kinesiology at the University of Utah. We recently outfitted the Sayu Lab for Biomechanics & Locomotion with a first-of-its-kind Caplex System™ including robotic ankle and pylon modules (PRO-002 and PRO-004, respectively).
Note you can read more about the refreshed PRO-002 and the all new PRO-004 in our blog:
- Introducing the PRO-004 Pylon Emulator: Revolutionizing Prosthetic Foot Research
- Product Refresh Announcement: Humotech’s PRO-002
We’d like to extend a huge thank you to Dr. Kota Takahashi for making it possible for us to develop the Pylon Emulator!
We hope you enjoy this behind-the-scenes look into Dr. Takahashi’s career, his interdisciplinary research approach, and how Humotech’s cutting-edge technology is transforming biomechanics.
Let’s dive in!
Personal Motivation and Role at the University of Utah
Candice Caputo (Humotech): What inspired your passion for biomechanics and human movement?
Dr. Kota Takahashi (University of Utah): I think that passion started early on. I was a high school student when I became interested in sports medicine because I was injured playing basketball. It started out as a low back pain. I started visiting the athletic training room to work with athletic trainers for rehab and became interested in studying the human body. That then made me want to study kinesiology, the study of movement.
I was at the University of Michigan for my undergrad, and as I learned more and more about the human body, I wanted to work with technology. Biomechanics was like a perfect merger of my interest in the human body while also integrating technology to improve human movement.
Candice Caputo (Humotech): Can you describe your current role and responsibilities at the University of Utah?
Dr. Takahashi: I am currently an associate professor in the Department of Health and Kinesiology, and my responsibilities are to conduct research in human movement and biomechanics.
A large portion of my responsibility falls into doing research, mentoring graduate and postdocs and undergraduate students, and teaching classes.
Right now I’m teaching classes at the graduate level for students in our program. Last semester, I taught a seminar/ journal club type of class, and I usually also teach biomechanics to the graduate students every other semester.
Candice Caputo (Humotech): What makes your research approach unique?
Dr. Takahashi: I like to have an interdisciplinary approach and I utilize all the degrees that I have accumulated. So I started out as an undergrad student in health and kinesiology, then my master’s was in biomedical engineering, and my PhD was an Interdisciplinary program in biomechanics and movement science.
There are a lot of aspects of kinesiology that I use. For example, anatomy and physiology. We want to understand how muscles and tendons interact, and how muscles and the skeletal systems interact.
But then in terms of assisted devices, we use a lot of concepts from engineering–a lot of design, mechanics, aesthetics, and dynamics to quantify human movement.
One area that is kind of a new area for us is trying to understand how vascular physiology biomechanics interact to produce human movement.
I think what makes our lab and our approach unique is that we try to take and borrow concepts from different disciplines. If we can say that we helped in bridging gaps between different disciplines, then I’d consider that a success.
Research Focus and Utilization of the PRO-004 Pylon Emulator
Candice Caputo (Humotech): Could you provide an overview of your team’s current research projects and how the Pylon Emulator integrates into these studies?
Dr. Takahashi: Yeah, so I’ll take you back maybe four or five years ago. This Pylon project started out as a collaboration with Dr. Matthew Major at Northwestern University. He had some interesting data looking at people wearing a compressible pylon for people with below-knee amputations.
Traditionally, prosthetic pylons are rigid devices. But Dr. Major’s lab had data looking at pylons that were compressible, almost like a shock absorber on a bicycle. I had specific expertise in quantifying the mechanics of prostheses, such as energy storage-and-return. So we teamed up and applied some of our analysis to the data that Dr. Major had at Northwestern. We started seeing some interesting trends, such as if you have a compressible pylon, it makes a huge difference not only at the pylon level but also in the intact structures like the intact hip or the opposite leg. So, once we saw that data, it kind of ignited a new interest in being able to do a follow-up study with robotic technology.
The main benefit of using robotic technology is that we can program the pylon to function any way it wants to. We can program it such that it’s as soft as possible. We can program it to make it as rigid as possible. We could also make or simulate damping elements, and so we really wanted to explore that avenue of research.
The work that Josh Caputo (President and CEO of Humotech) has been doing with Humotech was kind of the perfect technology to merge our interest in creating a better pylon for the amputees.
Candice Caputo (Humotech): Which specific features of the Pylon Emulator are most beneficial for your research objectives?
Dr. Takahashi: I would say initially the most beneficial aspect is being able to precisely control the stiffness of the device. For the first project that we’re doing, we want to simulate many stiffnesses–for example, a very stiff pylon, a very soft pylon, and anywhere in between.
Usually, anywhere in between is very difficult to do with just mechanical devices. The benefit of a robotic device using Humotech’s technology is that if we can just program it in a computer, we can set a stiffness value of X and then say give it 10% or reduce it by 10%. We have defined precision to be able to do that. So, I would say the first priority in our project is being able to do a fine precision study and seeing how the human responds to that.
Candice Caputo (Humotech): In what ways does the compatibility of the Pylon Emulator with various prosthetic feet enhance your research?
Dr. Takahashi: I think it’s huge. So we’re certainly unique in that we have not only the pylon emulator that Humotech developed for us, but we also have the prosthetic foot component.
So when we have the foot emulator in conjunction with the pylon emulator, then it’s almost as if we have a library of prosthetic feet integrated with prosthetic pylons.
I think it becomes a really powerful tool to study a host of different types of feet and the pylon together. One of our goals is to try to figure out for a given prosthetic foot, what’s the optimal pylon properties or vice versa. So, for a given pylon property, what’s the optimal foot component?
Candice Caputo (Humotech): Do you intend to conduct studies with both individuals with amputations and able-bodied participants using the emulator? If so, what are your goals for each group?
Dr. Takahashi: Whenever we’re testing new products, we should test it on ourselves first before we test it on a patient. So with the able-bodied participants, our goal is to do preliminary testing, see if it’s safe, see if it’s feasible, see if there’s some feedback that we can get from the participants before we test it out on a patient, and that I think helps with our efficiency and also safety.
We want to be sure before we test it out on patients that if we do this pylon and foot emulation, it’s going to feel safe to the user. But, the able-bodied participants can also give us opportunities to study things that we’ve never been able to study before because we have full control over what the foot property and the pylon properties are like so we can explore strategies that are absent in nature. So for example, shock-absorbing pylons. Humans certainly don’t have this but I really don’t know a species that has a telescoping leg. Muscles kind of function like that but an entire structure that telescopes and compresses, I’m not so sure if we have that. Probably for good reasons, but I’m really intrigued by the possibility that we can explore solutions that really aren’t seen across any species that I know of.
So we can do fun experiments on an enabled body participant. But then as soon as we start testing on patients with actual amputations, our goal becomes more about how do we maximize mobility for that participant? Is it a combination of compressible pylon and a foot? Or is it just a compliant foot with a rigid pylon? We don’t know the answer to that. And that’s why it’s exciting to get rolling on this project.
Candice Caputo (Humotech): How will you assess the impact of different axial stiffness settings on user comfort and mobility?
Dr. Takahashi: This is going to come down to a series of biomechanics experiments. To give you a snapshot of what our experiments might look like, we have a fully instrumented treadmill where we can measure forces on each leg.
Then as we are collecting the biomechanics data, we’re recording the forces, we’re recording physiological output, and we can actually make fine changes to the axial stiffness. When we make the changes to the stiffness, if that has a huge impact on say their loading patterns–“are they all of a sudden more symmetrical than they used to be before we changed the settings?”, then we have a pretty good idea that the stiffness changes that we made had a large impact on their ability.
So it’s a matter of collecting a lot of data at the same time when we’re getting biomechanical and physiological data as we make fine changes to the axial stiffness.
Candice Caputo (Humotech): What potential does the Pylon Emulator offer for the development and testing of custom prosthetic designs?
Dr. Takahashi: I would say the compressible Pylon idea isn’t new. A shock-absorbing Pylon has existed for over 10 years and I don’t know the exact origin. I don’t exactly know when it was first invented. The point here is it’s not new, but we’re building on what’s already been available to us.
What makes this particular device new is that it’s actuated, and because it’s actuated, the solutions and possibilities are pretty much endless. So we can simulate many passive components, we can simulate different stiffnesses, we could also simulate damping. We could also make it function truly like a robotic device in that it’s an actuated system. It could inject energy into the prosthetic leg. That’s a solution that we haven’t really explored, but that’s one area that I’m really excited about. After we get done with the first study, where we’re looking at the impact of stiffness, the next phase of the project could evolve into, well, what’s the combination of stiffness and damping, for example? Or, do we want to treat the prosthetic pylon as an actuated device that gives extra energy back to the user?
Candice Caputo (Humotech): How might your findings with the pylon emulator and the research that you’re doing influence the design and prescription of prosthetic devices in a clinical setting?
Dr. Takahashi: Yeah, so that’s a huge area in prosthetics. If we can say that we’ve made some contribution to accelerating the prescription process for prosthesis, that would be a huge outcome.
And so how exactly does our research contribute to that? Well, right now we really don’t know much about the potential use of shock-absorbing pylons. Some papers say it could help with the comfort of the user. Some studies say biomechanically, the participants’ gait looks better, but we really want to explore that further.
One question we’re going to try to answer is, are there certain activities that would benefit from shock-absorbing pylons? So, for example, the collaboration project that we have is funded by the Department of Defense. We’re testing individuals doing a lot of high-demand tasks, like load carriage, for example. Are shock-absorbing pylons more beneficial during low-carriage because you are tasked with greater weight demands? Or it could be that certain tasks, like walking up slopes or downhill could actually provide more benefit from the shock-absorbing pylon because there are much greater impact forces.
So those are some of the things that we’re trying to figure out. And then if we can show that there’s kind of an optimal combination of prosthetic foot stiffness and pylon stiffness, then hopefully we can find candidate prostheses that match closely the prostheses that we’re emulating in the lab setting.
Candice Caputo (Humotech): Do you foresee collaborations with other departments or institutions to expand the applications of the pylon emulator in research or clinical practice?
Dr. Takahashi: Yeah, so we’re already collaborating. I mentioned Northwestern University already. With this DoD-funded project, we have the Naval Medical Center San Diego involved. What excites me about that collaboration is that the San Diego site will work directly with military service members, so we’re going to get direct feedback from the stakeholders who are really important to our research design.
Once that project is finished, I imagine there could be other collaborative projects that could be forthcoming.
Candice Caputo (Humotech): What are the broader implications of your research with Pylon Emulator for improving mobility and quality of life for prosthetic users?
Dr. Takahashi: Well, the one outcome we hope to find is that the pylon, if we find the right combination of stiffnesses and features, then hopefully it’ll make a difference in somebody’s mobility.
I was saying earlier that perhaps it helps more in certain tasks. If we find what tasks are beneficial, then I think that would be an important finding that could benefit the prosthesis users.
Candice Caputo (Humotech): How does your work with the pylon emulator in research align with the mission of your lab?
Dr. Takahashi: The mission of our lab is using biomechanics and science to improve mobility outcomes. A large part of that mission is being able to understand what role assistive technologies, such as prosthesis, play in mobility outcomes. So that really fits within the mission of our lab very well.
I would say in a broader sense how it relates to our mission is that we took an idea based on our observation of human movement, and then we try to emulate some features of the human using a prosthesis. Even though we are using prosthetic devices to work with patients, we’re simultaneously improving our understanding of the human leg, why our human leg is designed in such a way, and why certain properties like shock absorption are so important for humans.
So even though we’re working with prosthetic devices and working with individuals with below-knee amputations, we hope that it contributes to a broader knowledge of how humans use our legs to move throughout this world.
Candice Caputo (Humotech): Looking ahead, what future research directions do you envision with the capabilities provided by the pylon emulator?
Dr. Takahashi: The first study that we have to do with the pylon emulator is in a controlled lab environment. Once we accumulate enough knowledge with the pylon emulator and determine what factors lead to improved outcomes in prosthesis users, then the focus might become: how do we make it portable? Are there candidate prosthetic devices already out in the market that we can start prescribing?
Conclusion
Dr. Takahashi’s work at the University of Utah exemplifies how cutting-edge technology and interdisciplinary research can drive advancements in biomechanics. With the integration of Humotech’s Pylon Emulator, his team is pushing the boundaries of prosthetic innovation to improve mobility and quality of life for individuals with amputations.
To learn more about Humotech’s Pylon Emulator and its impact on biomechanics research…