Ep 273: Why does my treatment work? With Dr Damian Keter

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[00:00:54] Dr Damian Keter, JOSPT The idea that personalized medicine or precision medicine is possible for things like pain, I think is a great pipe dream. I don't know if we're necessarily going to get there because of the complexities of pain. Hello and welcome to JOSPT Insights, the podcast that aims to help you translate quality research to quality practice.

[00:01:18] I'm Claire Ardern, the Editor-in-Chief of the Journal of Orthopedic and Sports Physical Therapy. It's great to have you listening today. We're often asking or answering the question, why, in clinical practice. Why does it hurt? Why does this treatment give me relief? Why is the problem not getting better? Sometimes it's easy to answer why, and sometimes it's not.

[00:01:44] In today's episode, Dr Damian Keter explores musculoskeletal treatment mechanisms and how to respond to the why question, even when the treatment mechanism isn't clear. Dr Keter is a physical therapist and board-certified orthopedic clinical specialist. He's an educator and clinical researcher for the U.S. Department of Veterans Affairs. Dr Keter's research explores patient responses to manual therapies, treatment mechanisms, and pain science.

[00:02:14] Dr Damian Keter, welcome to JOSPT Insights. Thank you. Thank you for having me. I'm very excited to be here. It's a pleasure to have you on the podcast, Damian. You've been on my guest list, top of my guest list for a while, so I'm glad that we could make this work out. You say that treatments for musculoskeletal pain often look simple, but it's difficult to explain how those treatments work. What do you mean by that?

[00:02:37] We recently did this editorial for JOSPT looking at this idea of treatment mechanisms and this idea that we used to think it was very simple related to why our treatments work. I provide this manual therapy. I must be moving this tissue, and that's why I'm seeing a clinical response. Or I'm needling this tissue through dry needling. I must be breaking up some type of tissue, and that must be why I'm seeing a response. Or even with exercise, I'm strengthening a tissue.

[00:03:02] The change I'm seeing in pain or our range of motion must be directly related to this improvement in strength. Now, the evidence just hasn't supported that simple A equals B relationship. The evidence is showing it's much more complex than that, and it's not one specific thing that's leading to the clinical outcome we're seeing. And I think as we see that, it aligns actually really well, as annoying as it is, that it makes it complex, it also aligns really well with the biopsychosocial model. And I'd like to explain why.

[00:03:32] Because the biomedical model, we thought, okay, there must be this pathology, this tissue problem that's causing pain. And if I can change this tissue problem with this treatment, then it should change pain or change this other outcome. As we've learned through the biopsychosocial model that, okay, there's all of this stuff, this neurophysiological stuff, this psychological stuff, all of these factors which influence this unique patient experience of pain.

[00:03:57] We're also learning that there's all of this stuff, this neurological stuff, neurophysiological stuff, psychological stuff that influences treatment response. And so we're seeing a lot of these things mirrored on the treatment side of things that are also these complexities which influence pain on the other side of things. And so I think it's complex because there's a lot of pieces there. There's a lot of moving parts.

[00:04:19] There's a lot of, you know, interactive systems that work together to not only produce pain, but also produce the treatment response we see. And I think the complexity comes from not only how many of those factors there are, but the fact that they're dynamic, that they're interactive, that they're constantly talking to each other. Things like the neuromuscular system and the neuroimmune system and the psychological system influencing, you know, some of these other things.

[00:04:43] And so, you know, I think that in itself makes this a very, very complex thing to not only understand ourselves as clinicians, but to explain to patients that want to know, right? It really reflects what we do as clinicians, doesn't it? That we're working with humans and humans necessarily are complex. So we're trying to, rather than say, if I fix this one thing, that's going to fix the problem. There's a whole bunch of very complex things that we need to consider. Right. Very much so.

[00:05:12] So then why does this matter? Why is it important to consider or understand the mechanism of the treatment you're delivering? If the treatment works, isn't that all that I should care about? Theoretically, yeah, right? Most of our patients, that's what they want. They want to say, I want to have less pain or I want to be able to walk more. I want to be able to, you know, reach to the top shelf. You know, I want to be able to do these activities. And so a lot of times that's what matters with patients, right? Those are the things that typically matter with patients is what they're able to do.

[00:05:38] But there is some good reasons of why we should understand treatment mechanisms and how our treatments actually work. And I think, you know, first and foremost, understand what a treatment mechanism is or a mechanism is more broadly. They're kind of the puzzle pieces. You know, when you talk about all those neurophysiological things and psychological things that I mentioned previously that influence the pain experience or all of these things that occur that influence the outcome. Those are all the treatment mechanisms or the pain mechanisms on the other side of things. So we talk about treatment mechanisms.

[00:06:06] We're talking about all of this stuff that happens when we provide a treatment to the patient. These biological things, you know, changes in neurological function, functional MRI changes, neuroimmune changes, all of these puzzle pieces that come together to influence that clinical outcome we see. Those are the treatment mechanisms. And so as we talk about, you know, the importance of these, a big part of this is us being able to explain this to the patient sitting in front of us, right? This fact that this patient in front of me wants to know, okay, you're pushing on my back.

[00:06:36] I feel a pop. What is this doing? Because patients want to understand that. And, you know, obviously the simple understanding for them is that, you know, you're pushing things back into place. You're realigning things. And we just know that's not true. So for us to be able to tell them it's not that, it's helpful for us to have an understanding of what actually is occurring. Because if we say, well, that's not it, but we don't really know, that kind of pulls us into that pseudoscientific realm where we're saying this works, but I have no idea why.

[00:07:03] And it kind of is this theoretical, theological type of idea of how these things work. And we know that's not the case. We know that there's very, you know, concrete things that occur. We just don't know what they all are yet. But the other side of this, you know, related to understanding these mechanisms that has a lot of potential, but also a lot of limitations is when you look at things like personalized or precision medicine.

[00:07:24] We talk about this concept of, okay, if I can figure out exactly what is contributing all these puzzle pieces and what is contributing to this person's pain experience or, you know, limitations. And I can match these two treatments that influence these things in the other way. I can give them a treatment that specifically targets their main problem.

[00:07:45] For example, if we talk about a patient with neuropathic pain and we're thinking that there's inflammatory irritation of that nerve or inflammatory markers that are causing this neuropathic type of pain or neuropathy. And we say, okay, we'll have this treatment such as a nerve glide that we know influences these neuroimmune markers, these inflammatory markers along this nerve. Maybe this is going to be the best treatment option for this patient to address this because I'm thinking that this is the mechanism contributing to their pain.

[00:08:12] And I'm thinking that this is a treatment mechanism I'm able to get with this specific treatment. The challenge with this, and when it comes to precision medicine and personalized medicine, I think the biggest challenge with this is this idea that these pain experiences very dynamic. Precision medicine was kind of, you know, originated looking at things like cancer treatment. Okay. And this idea that we can look at these cancer cells, we can look at this person's DNA, and we can say, based on all of these factors, this is the best treatment for them.

[00:08:41] Well, unlike, you know, cancer cells that we're not expecting to shift overnight and shift within a treatment itself, pain is very different. Pain, we know that the neuroimmune response, neurovascular response, all of these things are very dynamic, and they're influenced even simply by, you know, us talking to the patient during the subjective exam. And so I think the idea that personalized medicine or precision medicine is possible for things like pain, I think, is a great pipe dream.

[00:09:06] I don't know if we're necessarily going to get there because of the complexities of pain, but I think that understanding mechanisms is the bridge that could get us there. The more we understand of how these things influence the person's experience and how our treatments are actually influencing these things and leading to a change in this person's pain experience.

[00:09:25] As you were talking, Damien, I was thinking, we're moving beyond, I've got magic hands, trust me, I know what works, to I've got a scientific rationale for this plan, and we're going to test this thing and see what the outcome is, and then that will help us make the next decision. Some of these outcomes are really difficult to measure. Some of the neuroimmune responses, for example, are unlikely things that a physio in clinic could measure in a treatment session.

[00:09:53] How do you, as a clinician, when you're having these sorts of conversations with patients, trying to explain treatment mechanisms or helping people understand the changes that are going on in a treatment session or the decisions you and the patient are making together, how do you reconcile those two difficult things where sometimes you can measure some of these outcomes and sometimes you can't? So sometimes it's a bit like, trust me, in a sense, and other times it's, no, we can see these things because we can measure them easily. Yeah, and I think that's definitely the challenge, right?

[00:10:23] Is there's a lot of these, you know, we're looking at the clinical outcomes, and ultimately a lot of these studies are basic science studies looking at these, you know, neurophysiological things that occur. And this is where we're trying to pull towards studies that, you know, are utilizing basic scientists and clinicians to come up with outcomes that are both from the scientific standpoint and the clinical standpoint, we're able to tie some of these together. And that's where, you know, the National Institute of Health in the United States is doing some really strong work here, trying to pull some of these pieces together so that we're able to do research that really matters.

[00:10:52] But you're absolutely correct. From a patient standpoint, I can't tell a patient that I am changing the neuroimmune markers when I'm pushing on this tissue or we're doing this technique because it's all theoretical and it's based on that average patient that we see, right? And so I think first and foremost, when I have this conversation with patients is embrace the uncertainty surrounding it, right? Is this idea of we don't really know, but also try to emphasize what's been shown. And so I always kind of lead with the, well, it depends on who you ask, right? It depends on who you ask related to what's actually occurring here.

[00:11:21] But what we do know is there's this whole cascade of events that happens all the way from the brain to the body itself to the joints, all of this stuff that kind of occurs when we provide any type of treatment. And the combination of these things all add together to create your unique outcome. This kind of explaining it to patients this way also opens up the door for that patient response varying depending on the patient sitting in front of us. And so a lot of times I'll follow it up with that.

[00:11:47] That's why a lot of times we have to try a couple of different things and find what works with your system so that you get the response we're looking for, right? Because there's not a one size fits all. Then I typically like to tie this into other treatments that we use because I think a lot of times we think, well, PT, that just means we're in this pseudoscientific realm where we don't know how things work or what the best treatment is. But that's not unique to us, right?

[00:12:09] If you go see a practitioner for, let's say, blood pressure and they put you on a pharmaceutical for blood pressure and it doesn't work, they try something else and it doesn't work and they try something else. A lot of it is trial and error for the same exact reason, right? We know that different medications interacted differently with different people and we're ultimately just trial and error and trying to find that right patient response.

[00:12:29] I think also on top of the pharmaceuticals being tried and trying to get where we see a positive response for this specific individual, we also don't know how some of our pharmaceutical treatments work, but they've still been used for a long time. Acetamidaphin, Tylenol, they still don't know how that works. People take that all the time. There's a reason it's called a pain reliever because we know it relieves pain, but as they keep trying to check the different mechanisms there and figure out how it actually helps with pain, we're still not sure.

[00:12:57] And so, you know, if you look at the research there, they're in a similar boat where they're saying, well, we're not really sure why this is actually helping. So this isn't a unique problem to us as physical therapists or rehab professionals. Other professions and other treatments that we use for common conditions like pain and, you know, some of these other things, we're still not quite sure how they work and that's okay. But it's important for us to be able to still have a conversation with patients, embracing that uncertainty, but also making sure we can get across to them what we do know and what we think might be contributing to their unique experience.

[00:13:27] I really like how you frame that as there are some things in our clinical space and in our research arenas, we simply don't understand the mechanisms. There's still a lot of work going on, but that's not a license to do whatever you like and whatever you feel like just because you like to do a particular treatment. It's about marrying all of these different evidence, using evidence in as broad a sense as possible, all of these information sources to help you make an informed decision.

[00:13:55] And sure, you're not going to have all of the research available to guide you to make a very specific decision for a specific patient all of the time. But it's being intentional with how you're putting that information together is what I was hearing from you, Damien. As a clinician and a researcher, I get to see this. Research is based on averages. It's based on the average patient sitting in front of you. I don't treat averages, right? I treat an N of 1. I treat a patient that's an individual.

[00:14:21] And a lot of times, if you look at high-level research like clinical practice guidelines, a lot of these things that they say, you shouldn't use this. This isn't a good treatment for patients. It works really well for some patients. You know, there's a lot of things that might not work for the average patients. And maybe 9 out of 10, it does nothing for. But that 1 out of 10 patient I get in the door, that might be the best treatment option for them.

[00:14:44] And so, you know, I think balancing those things, balancing research, balancing what's good for the average patient or a patient similar to this individual in front of me with what's actually best for this patient in front of me. Based on, you know, their specific beliefs, expectations, based on their capabilities, you know, their motivation. What are they willing to do? What is the best treatment option for them individually as a N of 1, as a patient sitting in front of me, not as a number in a research study? And I think balancing those two, it's challenging.

[00:15:14] But it's also very, very important to give evidence-based care that understands the research, understands the evidence, but also understands when it's okay to kind of steer away from that. And I think we've seen that a little bit in the research recently where they're using these terms, you know, warranted and unwarranted variation, where they're starting to say, you know, it's okay to steer away from the clinical practice guidelines or best practice, you know, quote unquote best practice. If you have a reason, if it's warranted, it shouldn't be like you said, I just don't feel like doing this.

[00:15:44] I feel like doing this treatment just because I want to, even though it doesn't work or because it puts money in my pocket, right? That shouldn't be the reason you do a treatment. But if you say, you know what, I understand that traction isn't recommended for this patient, but you know what, they've had a really positive response for it in the past. And perhaps they've tried all this other stuff and, you know, they're already on an exercise routine and they're already doing this other stuff that I think this might be the treatment option for them. That's okay. Okay. It's not an always or never type of thing with treatments.

[00:16:12] It's trying to kind of figure out a starting point and what's best for that patient. That reasoning process is the challenging part and I suppose what we might refer to as the art versus the science of what we're doing as clinicians. It's a challenging job being a clinician, trying to keep on top of all this information, integrate it in real time, in a pressure setting, in a clinic with a person in front of you who's saying, I'm in pain, I need your help. But it's even more challenging for new clinicians.

[00:16:41] And I think the reason for that is, is we have to keep in mind from a, you know, the board's exams and, you know, some of these specialization exams and things like that. They're going to test you on primarily on one of the tiers of evidence-based practice, right? They're going to test you on that research because that's what they've taught you. That's what they've taught you in school. That's what they've instilled in you. That's what they can test you on. They can't test you on the other tiers of evidence-based practice, which is, you know, that patient perception, belief, things like that. They can't test you because those are all very unique to that one patient sitting in front of you.

[00:17:10] They can't test you on clinical expertise because especially as a new graduate, you don't have that yet, right? And so I think it's easy for us as we come out of school or we come out of some of these specialization exams and things along those lines to think very black and white about things. And I think I did that. You know, I came out and I was very much so if you fit this clinical prediction rule, I'm going to do this. I have to manipulate your spine because the research says I have to. Even if you're afraid of manipulation, right? I'm going to try to convince you this is what you need.

[00:17:39] And so I think it's easy to get stuck in that, right, out of school or, you know, when you're really focused on that research pillar of these things. And it is, like you said, it's an art balancing that and still understanding the value of those things while also looking at some of these other aspects as they evolve over time in clinical practice. This is the perfect segue for me to ask you about person-centered musculoskeletal care. Damien, we've skirted around this issue. We've talked about personalized medicine more from the medical care perspective.

[00:18:08] Let's bring this back to our sphere of rehabilitation and MSK specifically. What do you see as the hallmarks of effective musculoskeletal rehab care? I think first and foremost, it's understanding, again, that the person in front of you is not a number. It's not the average scene in research as we've talked about already briefly. I know Nathan Hudding has done some beautiful work here, several different publications looking at person-centered care, patient-centered care, and outlining a lot of the concepts surrounding it.

[00:18:36] I think really understanding with that patient sitting in front of you that it's not you taking care of the patient. It's not you telling the patients what they need. It's working with them. Once you start doing that, you realize you're able to build these therapeutic alliances where rather than you just dictating to a patient, this is what you need to do. These are the exercises you have to do to fix this problem. You come up to an agreement through shared decision-making.

[00:19:01] You come up with an agreement of what this care plan might look like for this patient based on their specific needs. Then you help coach them through this rehab process. I think once I started treating that way and getting away from this, I know better, I know what the research says, I'm going to tell you what you need, to actually looking at what the patient in front of me thinks they need and believe and things like that, it's a really nice way to create a care plan that works for them and that they're really compliant with. And so it's challenging because we're not a fast food restaurant, right?

[00:19:29] You can't have patients come in and just tell us what they want and do it. Ethically, we have to follow some guidelines and follow some evidence and things like that. But it's important for us to understand what the patient's thoughts and beliefs and how they can help navigate some of this stuff. Jared Powell did a really nice commentary actually in JOSPT recently on this concept of pluralism, right? In this idea that there's oftentimes a lot of pathways to get from where a patient is to where they want to be. And I think it's easy for us as clinicians to say, well, I know the best path.

[00:19:59] Person-centered care says, well, no, let me help work with this patient to establish what the best path might be for them. And ultimately, we can jump around between paths depending on how other things go throughout the rehab process. But understanding that they play a role in deciding this path to recovery as well.

[00:20:16] They did a study recently within the VA, and it was actually published in a journal of American Medical Association recently in JAMA, looking at this idea of a navigator program where they had patients in the VA system basically either get the care that the provider said you need to have, or these individuals were able to navigate through different complementary and integrative health, spinal manipulation, acupuncture, a lot of these treatments themselves based on what they thought and what they thought would be beneficial. And the outcomes were about the same.

[00:20:45] Ultimately, with this, we'd love to think we know better. But I think a big portion of this person-centered care is understanding that the patient probably knows better when they're dealing with their pain. We just have to keep them within ethical and safe guidelines of getting to that end point. And when you're a new clinician, we talked earlier about how all of this can feel quite overwhelming. You default to your training, which is very much, I do what the research tells me to do, and I don't really deviate from that.

[00:21:14] And this uncertainty is difficult for us all to deal with. None of us like uncertainty. And unfortunately, or maybe fortunately, we in musculoskeletal rehab are dealing with uncertainty a lot. Patients are dealing with uncertainty a lot. And when you're in pain, uncertainty is particularly challenging to deal with. Knowing what you know now, Damien, what would your advice be to younger version of Damien just getting out of PT school,

[00:21:42] trying to navigate this complex world, trying to do the best you can? Because I think we all have patients' best interests in the forefront of our mind and trying to do the best you can for patients. What would your advice be for newly graduated Damien? I think first and foremost, be okay with uncertainty. Be okay not knowing. You know, I think it's easy for us to think very black and white related to these things.

[00:22:06] And, you know, unfortunately, dealing with rehab, especially when it comes to dealing with the complexities of pain, is not that. It's not black and white. And so I think being okay with uncertainty, understanding that there's going to be things we're uncertain about throughout all of your clinical practice, is kind of the cornerstone. I think that's something that we really need to instill in new clinicians. Because even from an education standpoint, I think it's easy through physiotherapy programs to teach this is the way we do these things. But guess what?

[00:22:34] Five years out of practice, 10 years into practice, that's probably going to be wrong. Things change so quickly. And so I think emphasizing this idea that the knowledge is very dynamic or understanding is very dynamic and what's right today is probably going to be wrong tomorrow. And, you know, making sure people are very adaptable because of that, I think, is very important. I also think it's important for us to validate, not only to ourselves, but to patients, why they might feel the way they feel about certain things.

[00:23:03] When we talk about pain, it makes sense for all of us to want to know what is the physical cause of my pain because of our understanding of pain throughout our whole lives. You know, I step on a Lego. So it hurts. Therefore, you know, I understand that there has to be something causing this pain. Now, as we know, that's not always the case and it's not always that A equals B type of relationship. We need to appreciate why patients feel the way they feel. And so I always try to, first and foremost, reassure my patients that I'm here for you. We're going to work through this.

[00:23:31] We're going to try to get to this good place. But then I really like to validate to them and it kind of validates to myself as well why they feel the way they feel and why we used to feel that way and where we're moving with this. And so a lot of times I'll say, you know, I understand. It completely makes sense that you think that there must be something structurally there. I would as well. It makes sense that you're feeling this pain in the shoulder. You feel like there must be something structurally wrong in the shoulder. But a lot of times it's much more complex than that.

[00:23:58] A lot of times there's all of these pieces which are influencing this. And, you know, kind of portraying to them some of this information that we've talked about. Some of these complexities of these systems that are dynamic and interactive. But also emphasizing to them it's okay that we thought this way. It's okay as we move to understanding that's more complex than that. That, you know, we're going to work together to figure this out. Both from a treatment standpoint and in understanding how treatments work.

[00:24:23] Having that adaptability and having that ability to be okay with uncertainty are the keys there for me that I wish I would have known coming out of school. And I suppose too it's the we're working on this together. You're not alone. I'm here to help you and we're going to work together. And we're going to formulate a plan. So again, the person can see that there's a pathway forward. And as you said earlier, maybe that plan, the roadmap will change.

[00:24:49] We'll deviate off the path that we think is the direction at this point. And that that's okay too. And we're going to do that together. Damien, you've done some lovely writing on this topic of treatment mechanisms. People can find links to your work in the show notes. We'll also link to the article you mentioned from Jared Powell. I want to say thanks for your lovely writing, but also for bringing humility to this. Because I think that humility aspect to it and compassion for people is maybe a bit underrated.

[00:25:17] And I think you've really illustrated how that looks in practice and why it's so important. So Dr. Damien Keeter, thanks for joining me today on JOS 50 Insights. Thanks for having me. It's been a pleasure. Thanks for listening to this episode of JOS 50 Insights. For more discussion of the issues in musculoskeletal rehabilitation that are relevant to your practice,

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