Melanie Cole, MS (Host): Welcome to Better Edge, a Northwestern Medicine podcast for physicians. I'm Melanie Cole. And joining me today is Dr. Vehniah Tjong. She's an associate professor of Orthopedic Surgery at Northwestern Medicine. And she's here to answer the frequently asked question: does running increase the risk of hip and knee arthritis?

I have been asked this question so many times in my 35 years in the business, Dr. Tjong, so I'm so glad that you're here. We're talking about running and arthritis. And as we're discussing this potential link between running and the risk of hip and knee arthritis, what is the current medical consensus regarding the relationship between these things and the development of arthritis?

Vehniah Tjong, MD: Thanks for having me, Melanie. So, this was the major driving force behind why we did the marathon study in the first place, is that there really was no consensus to actually answer that question. So, we wanted to challenge the current dogma that many healthcare providers believe: that running does damage the joints and may lead to an increased risk of arthritis. But, as we found over the past decade, there's really been a nice growing body of literature to help support that perhaps it's not so much the major risk for developing arthritis.

Melanie Cole, MS: Wow. Okay then. I mean, runners have always wanted to know this and even long-distance walkers, but we're talking about runners, which is more of an impact sport. So, explain the biomechanical considerations and how running impacts the hip and knee joints and how this relates to arthritis risk. We're speaking to other providers, but not every provider, Dr. Tjong, and I found this out in graduate school, gets this biomechanics. They don't get that kind of thing and the exercise physiology of it all. So, explain that biomechanics of really how it works, because I remember in graduate school having to do all the drawings and everything. I mean, we had to lay it out with that impact. Tell us a little bit about that.

Vehniah Tjong, MD: I think the most important thing is to really understand the known risks of arthritis in the first place. So, we know that growing age, increased BMI or a heavier weight as a ratio to your height, family history of arthritis, as well as any previous surgery or injury to those joints. So, those are the main risk factors that we know. Now, in terms of the special biomechanics in running, we know that running mechanics is really paramount. So, having good core control, good core stability and then working towards your peripheral muscles, making sure your glutes, your hamstrings, your quads are in an appropriate condition, and then, finally, even foot intrinsics. And as we talked about previously, even footwear can really help to make these running mechanics sound. Now, we do know that cross-training, especially if you're training for long-distance runs, such as marathons or even ultramarathons can really help to achieve this. So, I think that is sort of the main takeaway here in making sure that your mechanics are sound so that it really doesn't increase your risk for injury.

Melanie Cole, MS: Well, let's talk about some of the factors and types of running. Some people are trail runners. Some people are barefoot runners. Some people have really great shoes on. But then, there's the cement or the gravel. There are all different factors that come into play when you're talking about running, Dr. Tjong. Speak about some of those things that you would look at as an orthopedic surgeon and say, you know, if you're going to run on the gravel or if you're going to run on the cement, you want to make sure you have really good shoes and excellent arch support. Speak about some of the factors you specifically look to.

Vehniah Tjong, MD: I think anecdotally, if you're running on a softer surface like trail or grass, you automatically think this has got to be better for your joints than running on hard concrete or any harder surface. But if you look to the literature, there really hasn't been an impactful difference that is seen statistically to actually make the argument for harder surfaces increasing the risk for arthritis.

So, I think we're going to turn you back to the biomechanics of it all in that if you're trail running or running on different planes, inclined planes, side-to-side planes, rockier surfaces, it really requires more core control and intrinsic muscle power to actually make sure that your mechanics stay sound. But as far as the literature goes, there really hasn't been anything proven that says running surface increases your chance for arthritis.

Melanie Cole, MS: I'm so glad to hear that and be able to take that forward to my clients and patients. Now, what about footwear? Because boy, there's a lot on the market today and they keep getting better and better. Are these kinds of things, and any other preventive measures or techniques that runners can look to, can they help to reduce that risk? I mean, the footwear is getting more and more technology all the time.

Vehniah Tjong, MD: In fact, I think that this is where we turn to our podiatry colleagues, our running footwear specialists, really to look at your arches, how you were born, and how your alignment all the way from your spine to your in and to your foot really help you become the best runner that you can be. Now, I don't think that there is a specific brand of footwear that's better than others, but that's why we try to cater it to specific runners, especially when it comes to just running in a straight line or having to incorporate some of that side to side or pivoting type of action. So, I will say that not all footwear is created equal.

Melanie Cole, MS: And certainly, I agree with you that this is a multidisciplinary approach with, as you say, our running specialty colleagues. This is the way that runners and real, true runners can get the most out of what they're doing with the least amount of risk. I mean, there's always going to be some risk. So, let's talk about warning signs. When a runner goes to see their trainers, their orthopods, their podiatrists, any of these things, what are some of the symptoms, red flags, that you want runners to go, “Whoa, you know, this is not what it's supposed to feel like.”

Vehniah Tjong, MD: I think in general, the notion of arthritis coming on all of a sudden is something that needs to be explained. Arthritis is something that really develops over time and the body tends to adapt to the changes in their joints and their muscles and their tendons. The biggest warning signs that I would alert most athletes and most runners of is joint swelling. So if you are training, if you're running and all of a sudden you have swelling in your joints that can't be explained or really it doesn't go away, that's the time to seek the advice of a healthcare professional to really understand why is my joint swollen and what should I do about it?

The second thing is really that it is important not to push through pain. So, runners in particular, or any impact athletes, can be predisposed to stress injuries to the bone. And so, you talked about the multidisciplinary approach, and this is where bone health really comes into play too. To prevent stress injuries, especially for runners who train in the northern hemisphere, having the appropriate level of vitamin D and calcium can help reduce these risks of stress injuries to the bone. But if you do have pain, if you do have swelling, that's the time to go see one of your healthcare providers.

Melanie Cole, MS: Running up to the pain, but not through it. Are we still saying that? Because I think that that's still a good rule of thumb. Once you start to feel that pain working through it, and we know that with things like the Chicago Marathon, the Boston Marathon, these runners, they are hardcore and they run through some of the most intense pain I cannot even imagine.

As we get ready to wrap up, and I just love this kind of episode, Dr. Tjong. Recommendation for physicians who have patients who have a history of hip or knee issues but want to continue running without exacerbating their joint problems and for physicians who are working with maybe new runners or people taking it up, weekend warriors who are deciding to start to run now, best advice for them on working with these patients to hopefully stave off some of the arthritis that could come in the later years.

Vehniah Tjong, MD: I think the main focus should be on focusing really on what we can control, so these modifiable risks. So, we know what we can control, is to maintain a stable, healthy weight, especially throughout life, but also in training and any athletic activity, as well as proper mechanics. Again, we kind of continue to go back to that same notion in that, if you're training, train properly. And if you don't know how to, it's very easy to find the help to do so. Not only through our physical therapists, occupational therapists, strength and conditioning coaches, but all of these resources can help healthcare providers teach their running athletes how to prevent injuries in the future, and also to advise their runners of the good healthcare benefits that running has been shown over and time and time again, helping to decrease diabetes, decrease cardiovascular risks, but also help balance mental health issues as well.

Melanie Cole, MS: Absolutely great information, Dr. Tjong. Thank you again for sharing your expertise. You are an excellent guest. And to refer your patient or for more information, please visit our website at breakthroughsforphysicians.nm.org/ortho to get connected with one of our providers.

That concludes this episode of Better Edge, a Northwestern Medicine podcast for physicians. Please remember to subscribe, rate, and review this podcast and all the other Northwestern Medicine podcasts. I'm Melanie Cole. Thanks so much for joining us today.