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[Physio Explained] Exercise for knee and hip OA: key findings from recent research with Dr Anthony Teoli

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In this episode with Dr Anthony Teoli, we explore a recent paper looking at therapeutic exercise for knee and hip OA. We discuss:

  • Treatment effects of specific interventions
  • Simplistic views in patient improvement
  • Potential mechanisms for patient improvement
  • Role of anti-inflammatories
  • Exercise as treatment for knee and hip OA

👉🏻 See Anthony’s full Research Review here - https://physio.network/reviews-teoli

Dr Anthony Teoli has a Master's in Physiotherapy and a PhD in Rehabilitation Science from McGill University. He works as a physiotherapist specialising in knee osteoarthritis research and clinical outcomes post-knee replacement. He is also the founder of InfoPhysiotherapy, an online platform offering evidence-based courses for rehabilitation professionals.

Reference to article: Runhaar J, Holden M, Hattle M, Quicke J, Healey E, van der Windt D, Dziedzic K, Middelkoop M, Bierma-Zeinstra S, Foster N, The STEER OA Patient Advisory Group; The STEER OA Patient Advisory Group (2023) Mechanisms of action of therapeutic exercise for knee and hip OA remain a black box phenomenon: an individual patient data mediation study with the OA Trial Bank. RMD Open, 9(3). 

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Our host is @James_Armstrong_Physio

UNKNOWN:

Thank you.

SPEAKER_00:

The findings basically suggest that there's quite a lot that we don't know about why a patient's pain or their physical function may or may not improve through the use of exercise. So I know sometimes we tend to maybe attribute a little bit more than we hope to the specific effects of a certain intervention. But it's important to embrace this sort of uncertainty and appreciate just how complex the actual treatment effect is.

SPEAKER_02:

Welcome to today's episode of We'll also unpack the potential mechanisms behind how exercise can alleviate pain and improve physical function in patients with knee osteoarthritis. Plus, we'll hear about the latest best practice recommendations for exercise in managing knee osteoarthritis. Anthony's research expertise, particularly in gait biomechanics and outcomes following knee surgeries, has led him to present his work internationally and today he's here to share valuable insights with us. So stay tuned for an insightful conversation on therapeutic exercise and its impact on knee osteoarthritis. I'm James Armstrong and this is Physio Explained. So we are going to chat today about a research review that you've done for the Physio Network looking at an article titled Mechanisms of Action of Therapeutic Exercise for Knee and Hip OA remain a black box phenomenon. And this is an individual patient data mediation study with the OA trial bank, which is quite a mouthful. I thought we'd kick off with a bit of context as to What does all that mean? And then we could go into what the findings are for this article.

SPEAKER_00:

Sure. Yeah. So something that's a little bit different with the study is they did a individual patient data analysis from randomized control trials. And the way that that's a little different is that normally you can normally either try and combine all the participants from all the randomized control trials. Well, in this case, the way it works is the original research data for each participant is included in the study. So it's just done a little bit differently. So in this study, what they did is they included data from 12 of the 31 randomized control trials that were part of the steer away program, basically.

SPEAKER_02:

Brilliant. So we're going to dive first of all into actually summarising the findings of this article. Then we're going to talk a little bit about why those findings are important and some of the clinical application of those. So should we dive into what is this article finding and why is it so interesting?

SPEAKER_00:

So while the objective of the article or the study was to actually evaluate mediating factors for the effect of therapeutic exercise on pain and physical function in people with knee and hip osteoarthritis or OA, and a mediating factor is basically just a variable that explains explains the process in which two variables are related. So the process through which exercise may improve pain or physical function, for example. And what they found is that in people with knee osteoarthritis, knee extension strength only mediated about 2% of the effect of exercise on pain and physical function. But they also found that ROM or range of motion and proprioception did not mediate a change in outcomes, and nor did knee extension strengthen people with HIPAA. So the reason why this is really relevant is just that The findings basically suggest that there's quite a lot that we don't know about why a patient's pain or their physical function may or may not improve through the use of exercise. So I know sometimes we tend to maybe attribute a little bit more than we hope to the specific effects of a certain intervention, but it's important to embrace this sort of uncertainty and appreciate just how complex the actual treatment effect is. So normally, if you were to break the total treatment effect down, you have three components. You have your non-specific effects. These are not inherent to the treatment and they just occur naturally over time. So an example would be the natural history of the disease. So how would that condition have improved over time without treatment? There's also contextual effects. So there's patient expectations, the clinician-patient relationship, the setting of the intervention. So these also produce a treatment. effect, but that's independent of the actual specific effect of the intervention itself. And the third is the specific effect, which is the effect inherent to the treatment, which in this case is exercise. So it's the physiological mechanism of action of the treatment itself, basically.

SPEAKER_02:

That's quite interesting, especially as physiotherapists, we're often aiming for certain things that you've mentioned there, such as improving the knee range of movement, improving knee extension strength, with the mind of thinking that that's the thing that's going to improve our patient's function and pain. And this study is saying that it might not just be as simple as that.

SPEAKER_00:

That's exactly it, yeah. And interestingly, there has been a bit more research looking at the, I guess, placebo effect or the proportion of the total treatment effect that is not attributable to the specific effects of the treatment. And what previous research would suggest is that that's less than 50% of the actual treatment effect is specific. So it It's humbling to say the least. And as clinicians, I think we do tend to overestimate how much of the specific effect of our intervention was responsible for the reason why the patient improved. But at the same time, it's something that's important to understand that there's other factors at play. And like you said, it may not be as simple as we once thought, which is we have to embrace that uncertainty.

SPEAKER_02:

Absolutely. And we're seeing that an awful lot into the research that's being done over the last five to 10 years, I think, and maybe more. In terms of clinical implications of these findings, how do you think this might change practice I

SPEAKER_00:

think it has more to do with maybe acceptance on our part. I think it's more just realizing that limitations and maybe not being quick to attribute the improvement that we saw to anything that we did necessarily, or it's possible that we had a role to play. Like I said, because it's more complex, I think something as simple as my patient had a quadriceps muscle weakness and I prescribed a knee strengthening program. And within two weeks, the pain is gone. It's because the patient got stronger. It's a little too simplistic. There's often a lot more variables at play. And I just think the clinical implications have more to do with just keeping an open mind as to why that patient may have improved and maybe not putting too much emphasis on the specific effect of the treatment that we administered.

SPEAKER_02:

Do you think also that it might actually take a bit of the pressure off clinicians in worrying about whether or not we do get extra strength or whether we do gain range of movement with our exercise program?

SPEAKER_00:

Yeah, no, I definitely think so. And I think in a way, I think that that's a great way to put it. It's that we have maybe these lists of things that could help, but they don't need to improve for pain or physical function to improve. So it does kind of take a bit of the pressure off in that sense. So yeah, I think that that's a great way to kind of put it is that there's a We have other things helping us in a way. But yeah, I think that's an interesting point there. Absolutely.

SPEAKER_02:

We can make it maybe think more about what we actually going to be able to get our patients to do that they want to do that means something to them and all of those other things that we like about patient-centered care. So we're kind of looking at what aren't the potential mechanisms. What do we know about what could be some of these potential mechanisms and what is going on with this then?

SPEAKER_00:

There's a lot of theories and I would say that in the moment, it's something that's Not very well understood, but there are potential mechanisms of action. I just want to highlight the word potential because these are kind of suggested, if you will. One of them is this mechanism called exercise-induced hypoalgesia. So it's basically a generalized decrease in pain and pain sensitivity that occurs during exercise and for a bit of time afterwards. You could also have the opposite, which is exercise-induced hyperalgesia, which can happen quite often in more chronic pain presentation. That would be one potential mechanism. But again, a lot of this remains to be validated. When we're discussing mechanism of actions, is there really just potential? The second one is habituation or increased load tolerance. So the idea here is the body can adapt as long as the load applied is within the body's capacity to adapt to it. So if we're kind of progressively overloading the tissues, there should be some adaptation happening, assuming we're not underloading and assuming we're not surpassing their capacity to adapt or hitting their limits and essentially inducing a flare-up. So that would be a second mechanism. A third one, which is more maybe recent, but anti-inflammatory. So we know that, for example, in the case of osteoarthritis, There are some more systemic variables that are really important, systemic inflammation as well. So these are important to consider. And exercise can help to reduce this systemic inflammation. associated with osteoarthritis, but also associated with the comorbidities that patients with osteoarthritis tend to have, such as cardiovascular disease, diabetes, obesity, etc. So exercise kind of has more of a multifactorial effect. It could have a multifactorial effect. There's also improved general health and fitness benefits. So there's potential for weight loss, there's potential to improve strength, proprioception, balance and motor learning, aerobic fitness. So again, these are all examples, but we don't know necessarily if one of these is that key. key variable that might explain that relationship. There's improved psychological health and well-being and increased self-efficacy and placebo effects, obviously. We just discussed that before. But we don't really know which of these, if any, has more of a predominant role in explaining why one patient will get better with exercise and one won't. So it's a bit tricky, but there's more that I would say that we don't know than that we do know. But there are quite a few potential mechanisms that have been proposed, basically.

SPEAKER_01:

Well, it brings...

SPEAKER_02:

true to me is how on earth are we ever going to know because of the complexities in the variables and how do you control for these and how on earth did you put a study together that could possibly look at this and come out with an answer?

SPEAKER_00:

It's quite a beast to tackle. It's difficult because the other thing that's important to consider as well is that there's other factors at play as well. So it's one thing studying exercise and the potential effect on pain and physical function, but in real world practice, there's other things that are happening too. There's patient education, which will change how things are done at home. For example, if we're avoiding triggers and we're better understanding what tends to bother the knee, for example, and just pulling back lightly and things start to calm down and do better afterwards, was it the exercise or was it the load adaptation that we imparted in that patient education? So there's I think there's the research component where we try and tease out the individual effects, but in real life, exercise is not given in isolation. And on top of that, we might be also working on several of these mechanisms. So if we have someone who we prescribe an exercise program to who loses weight, All of a sudden, we're talking improved health benefits. We're working on the comorbidity burden as a whole. We're helping to reduce systemic inflammation. There might even be some improved psychological health that goes along with it. So we're tackling four of those seven or eight potential mechanisms at the same time. So when the patient gets better, how do we tease them out? And I don't have that answer. It would be quite the complex study. And it's probably why we know so little about it. But I think there's ways to control certain variables and There are definitely better researchers out there for that task. But I think we're in the process of chipping away at it from what I'm understanding. But I do think there will be a big chunk of it that might be a little more unknown. But I think that's the beauty of the research. And I find it fascinating as things start to develop and we start to get a better understanding and chip away at it. So I think it's something that maybe we'll have more answers in the near future. But will we have the entire picture? I think that that might be tough.

SPEAKER_02:

Brilliant. Yeah. And it's the exciting bit about science. I'm going to get comfortable that we don't know. Hopefully, we never will know. then that means there's always questions and there's always research to be done. And that's exciting. It's that curiosity. Yeah, absolutely. So I think leading on to our final point now, Anthony, in terms of, I suppose, really quite an apt question is, what are the current exercise best practice recommendations for patients with knee and hip arthritis? And where are we right now as we stand?

SPEAKER_00:

Well, I think the most important thing is the first line intervention for all patients with knee and hip OA. is basically exercise, weight loss, or weight management, if it's indicated, and patient education. So I'll focus on the exercise bit. It's really the only treatment that we have for patients with NeoA that has been extensively studied, that is unanimously recommended by all clinical practice guidelines, and has so many added additional beneficial effects. So physical, mental, you name it, basically. And obviously, because it's the best that we maybe have at the moment, given those points, the effect size is, when we look at you know, the effect of exercise on pain, physical function in patients with an EOA, for example, is in the small to moderate range. And it's not there to help everyone. It's not, you know, a magic kind of bullet that's going to help every single patient with knee and hip OA, but I do think that every single patient with knee and hip OA should at least be offered it and at least give exercise a try, obviously prescribed by a healthcare professional, but for at least eight to 12 weeks as done in most studies, two to three times a week and have it individualized to them and what they enjoy. So there's no really best exercise for patients with knee and hip osteoarthritis. It seems to be I think the most important one is the one that gets done and what patients enjoy and what they can fit into their schedules. So I try and make it as realistic as possible for them. I literally outright ask them, if I were to do this for you and it would take you 20 minutes and I would ask you to do it three times a week, would this be feasible? And then they tell me, yeah, yeah, that's perfectly reasonable for me. And I would say, perfect. And sometimes they'll say, actually, I would almost prefer it be shorter and I'm able to do it for more frequently. And I said, no problem. You know, I'll adapt it to their schedule as well. I think just getting them to do it so that we have the best idea of whether or not we gave it a fair chance is probably the most important. But like I said, it's the best that we have in the sense that it's the most extensively studied and it's the only intervention That has all those additional benefits and that patients can do on their own. So obviously there are other interventions that we can administer, but the patients will rely on us for them. And the goal is eventually for patients with knee and hip OA, then it's a bit more chronic or long-term. The goal is to kind of put them in the driver's seat and give them the necessary strategies so that we're there to guide them eventually, but they could do a big bulk of the self-management on their own with time.

SPEAKER_02:

Definitely, Devin. And I think this was, again, what makes it this really useful is that we can find out maybe from our patients what exercise they've liked to do in the past. Maybe what have they recently given up for reasons that aren't necessarily appropriate because they may just be afraid. So we can tap into the things that are interesting to them that we'll say will increase that adherence because we know that there isn't something that's the one thing, you know, knee extensions in the gym aren't necessarily important.

SPEAKER_00:

Yeah. What it is at the end of the day is it's not necessary to kind of box them in with a certain type of exercise. For me, what I really look at is How active have they been recently? Because that they did maybe, you know, that they were active cyclers or runners 10 years ago doesn't, I mean, it helps me to a certain extent, but if we've been out of the game for a long time, I'm more interested in where they're at now. How much pain do they have when they move, especially in weight bearing? Because that's the primary complaint and their preferences. Usually I'd kind of just put those all together. And I obviously, I have, you know, my biases. I do tend to kind of lean towards the strengthening, but in patients with knee and hip OA, sometimes it's just as simple as a walking program. If they don't have any equipment, it's a walking program. I kind of phrase it as like a two to three exercises that are in a way functional. You know, your typical, your squats, your step up, step down, your lunges. And it's in a way that it's not necessarily like I went to the gym and did an hour of legs, for example. It was just a little bout of 15 minutes just to get the knee moving, but they don't see it really as like I'm doing strength training three times a week for an hour and a half. So I try and make it, especially if they don't particularly like strength training, I do think that those exercises are beneficial, but I'll try and include them in a way that's feasible for them as well.

SPEAKER_02:

And I suppose we've also got to think about what are the other benefits of resistance training for this patient population?

SPEAKER_00:

That's the thing, yeah. There's the physical activity component, there's the aerobic component, and obviously there's the strength component. And I think it's important to kind of tap into all of them, but we don't necessarily need to do a full-fledged three times a week leg workout of an hour, an hour and a half. If people don't have access to a gym, I try and keep it 15, 20 minutes and they do it a bit more often. And I think most patients, because it's just like a bite-sized workout, they're able to just put it And as long as it's well tolerated, they seem to enjoy it in a sense that it's like, oh, I'm able to do more reps. I'm able to get out of a chair a little bit easier, get down to the floor a bit easier and get back up. Little things like that that I think are important.

SPEAKER_02:

Brilliant. Anthony, thank you so much for your time today. We've covered so much and I think there's a definite clinical takeaway there for everyone listening that will probably make our practice a little bit easier, a little bit more options open to us and not necessarily going to change things massively but just give us a little bit of reassurance on what we're doing with our patients and how the outcomes are sitting with what we think at the moment may be slightly differently. So Anthony, thank you again so much and for those listening, do check out Anthony's research reviews. He's done plenty for us and as I was saying off air to Anthony recently they've been really useful to me with some work I've been doing for an essay so thank you very much again Anthony

SPEAKER_00:

I really appreciate it thank you so much for having me

SPEAKER_02:

take care