Episode 130 | Your Uninjured Side Hurts. Why?

Show Notes:

In this episode,  we cover a very common question we get – why does the uninjured side hurt? If this is you, this episode will help shed some light on why that might be happening and what you can do about it.

What is up team? Getting straight into the episode today: Your uninjured side hurts, why? I think that this is something that comes up very often and something that we see in this process. And we get a lot of questions around for many different reasons. I want to dive into this topic today to help bring some education around it, to understand what is going on, why you might be feeling this, and why your ACLers might be feeling this. And this is something that I think can help a lot of people. It’s crazy that sometimes we’ll get people where they start to say, no, actually, my ACL side is not bugging me. It’s actually my uninjured side that is giving me a lot of trouble. And sometimes instead, what they do is “they rob Peter to pay Paul.” And that’s just a phrase that’s basically like you’re passing around one problem to another. And then therefore it’s not very productive. 

Today, I just want to share why this might be happening. Let’s get right into it. First off, you might be post-injury or post-op, and this is where we probably see this the most. And it makes sense, right? You’ve just had an ACL injury. The knee is just not functional like it normally is. It’s swollen, it’s painful, and you’re hesitant to move it. There might be some instability going on. And then post-op, it depends on your process and the procedure, so many variables. But a lot of the time you come out of surgery and your leg is straight. You’re not bending it. And therefore you’re in that position. You might be locked in a brace. Therefore, you’re typically having some sort of weight-bearing restriction to some degree. You might be non-weightbearing if you had a meniscus repair or if you’re post-injury. That’s the same thing too. A lot of times people are scared to put weight on it.

Again, all these factors play into it. But basically, non-weightbearing, partial weight-bearing, it might be toe-touch weight-bearing which is just a little bit, and then it’s weight-bearing as tolerated. Basically, how much can you bear and make sure that the knee is not super painful or continuing to swell up more and more and progressing over time? With that said, you’re going to be limited. One leg is unable to pull 50% of its weight, in theory. When we’re walking, usually 50% of the weight is done on one side versus the other side, just in theory. Especially, if we have weight scales, you think about it when we’re walking, doing anything, double leg, for the most part. It’s usually an equal-equal side until you have this injury. And then there’s a distribution of, okay, I can’t load my leg on the ACL injured or operated side, so now I have to carry my weight on the uninjured or unoperated side. And sure you might be putting some weight down, but the way you’re moving is definitely different than when you are not injured or not post-op.

All this comes back to the injury itself and how your body reacts. Often you’re limping or as I had mentioned, non-weightbearing and on crutches. Regardless of when you move, your body is focused on completing the task in front of you, not optimal stress distribution. And so that means that stress and work are put on different areas, other areas outside of this knee because we’re trying to protect the loading and stress going to it. The pain, the swelling, maybe the fear of the instability, and the restrictions are causing you not to put as much weight through that leg. Therefore that stress has to go other places because we don’t just magically reduce stress or get rid of the stress when you’re normally walking with two feet, that has to go to other places. And so often the unaffected side has to do a lot more walking, navigating stairs, sitting down. Any daily activities you can think about that involve using your lower body. Your lower leg, the unoperated, uninjured side is doing a lot of that work.

Now, let’s say your knee can barely bend and you’re weight-bearing some on that foot. You’re just hobbling along. Now to walk, we need one requisite that is important, if we’re talking about knee bending, which is roughly to walk normally, somewhere around 65 to 75 degrees of knee flexion or that knee bending. Let’s say you can only get to 40 right now, but you’re trying to still hobble around, and put weight on that foot. Our bodies are super smart and we’ll learn how to complete the task however it needs to be. If it’s not there, we’ll do whatever it takes to get from point A to point B. Swinging your leg around could start to put a lot of stress on your hip flexor and abductors on the ACL injured or operated side. But then more stress is going to the unoperated or uninjured side because it’s having to do more of that work.

And then let’s say you have to hike your hip in order to go through this process. You’re using your oblique and lower back a little bit more surrounding hip muscles, taking your ankle and turning it out as you walk to reduce knee bending. Therefore your hip external rotators and maybe the medial side of your knee are actually taking a little bit more stress. Side bending our torso as we walk to just hobble around. Again, oblique, low back surrounding hip muscles, and then you’re just hobbling. Many different areas and depending on how you’re using your crutches, if you’re leaning on them with your armpits versus really using your wrist, maybe you’re leaning on one side versus the other. It’s just not normal for our bodies and we have to take on this new distribution of stress and we just figure out how to do it. And that’s all because we don’t have enough knee bending, for example, in this case. But this isn’t something that our brain is thinking about or we’re thinking through as an ACLer, the goal is for you to just hit these requisite areas and make sure that you are able to essentially pass what you need, to be able to meet the demands of whatever it is you’re doing.

For walking, we need 65 to 75 degrees of new flexion, we need full extension, and quad-active control. Those are different pieces that we need to make sure that is a part of this process. If we don’t have it and we continue to accumulate reps with that and especially a lot of steps, you’re going to feel it. Our bodies are master compensators. And I can say this with now seeing thousands of athletes just across the board with different conditions, moving with pain, with different injuries, especially ACL, of course, we figure it out. We’re just able to do the thing. And if I lined up 10 people right now who are, let’s say two to three weeks post-op. And I ask them to just go walk, they’re going to all walk a little differently.

Sure, there might be some overlapping patterns. But based on their experience, how they’re doing at that time point and let’s say that they don’t have everything just locked in with their gate yet, they’re going to look different. And therefore, they’re distributing stress to different areas. They might all complain of different things that are going on as they are working on this gait, but then accumulate more reps with these compensations that they’re feeling.

Now, you might say like, I don’t want to compensate and do this. It’s totally normal for this to happen. You don’t really have a choice to some degree because of the constraints of the injury and the surgery. It’s natural. It’s just a matter of like, okay, if you are actually hurting on the uninjured side or other areas, we need to make sure that that is taken care of so you don’t create just another problem that you need to work through, and around. The concept of this is that the body just self-organizes to figure out the movement or the task that’s in front of us and really doesn’t care what’s moving or what’s working to do it unless you’re really intentional about it. And that’s where slowing things down, making sure the right areas are working, you’re having the proper mechanics and the positions and postures, and then ingraining the pattern and then ingraining a little bit more intensity or power as we say it, the three Ps. But you still need to have access first to this range of motion and the strength at the very least. 

This is what we call movement options and movement capacity. We have to make sure that we have that available. Because if we don’t have it available, you’re not going to be able to access it. So that’s why we need to make sure that that’s there. A simple example here is that if you’re trying to get your heel pop and terminal end range extension, you can’t passively with a relaxed quad. If someone puts their hand on the end of your thigh and tries to lift up your heel if you can’t just lift it there and passively get there without activation, you don’t have access to that range of motion yet. If you’re trying to activate it, guess what? You’re not gonna really get there because you don’t have the passive solution or the option available to do that. Therefore, the active piece, contracting the quad isn’t going to get there. That’s why we do a passive pool into extension first and overpressure, and then we try to contract into it. It’s stretching into a new position and then loading that new position and activating within it. We have to have it passively first and then actively. But that’s basically in a nutshell movement options and trying to make sure we have that active capacity and strength to get there. 

Another great example of this is the split squat. Someone might lack the proper quad strength to allow the knee to move forward past the toes, or maybe for other reasons, like knee pain, limitations in knee flexion or bending, etc. Instead, you’ll keep the shin very vertical, so straight up and down to shift the stress and make sure that the hamstrings and the glutes are working. You’re taking stress off of the front of the knee, and part of that could be because of the pain, or hesitation. 

A lot of times what we see is that it’s because people’s quads aren’t strong enough to be able to handle the position, so their bodies self-organize and figure out how to avoid it. The way you avoid it, but still complete the task is by keeping the shin vertical and then being able to bend at your torso in order to shift the stress and the moment arm to the hamstrings and the glutes is probably the most classic ACL compensation outside of shifting your butt back during a normal squat or to the unoperated side. If you’re not getting feedback on your movements and strategies, then you’re “doing it,” but the intent and the goal of the movement aren’t being executed the right way to get the outcome and stimulus we want. And I can name this with 20 different things off the top of my head with ACLers where I see them doing this right off the bat just because of the nature of the injury and the surgery and just the downsides of it. And then that’s why this process is so important, especially after injury and especially after post-op. Because yeah, they might’ve taken a donor tendon to be able to create your graft, and then you’re also kind of playing catch up with a lot of the different areas and pain and swelling. Therefore, this is normal in this process.

Today, I’ve shared a little bit about why the uninjured side might hurt. But I want to dive a little bit deeper into this topic so you can have a little bit more of a practical approach to this and understand this principle that will really help to be able to, okay, this is why this might be going on. And as I mentioned, you’re offloading stress or load to the uninvolved side many times, especially early post-op and post-injury. Then this, a lot of time, comes back to something called load management. This is basically in a nutshell managing stress or the load being placed on your body. Volume is usually the biggest factor here. It’s very rare that it just happens in a single bout or a day. But it can. The thing is, is that we just have to watch the spikes in volume. 

And what I mean by that is just a lot of repetitions, and it might not be at a high intensity, but it’s a lot of repetitions of doing X thing or a certain thing. Going to a city or doing a big hike, untrained is a very good example. You go to a city, you walk around, typically a lot more to explore the city. If you’re not a big walker and you don’t have a high step count, you go to this new city. This is something that people feel all the time. They finish the trip, or the first day or two. They wake up and they’re like, wow, my legs are sore. And it’s usually because they’re taking, instead of maybe 5,000 to 10,000 steps a day, they’re going to 20,000 to 30,000 steps. And if you add something like a hike or anything else involved, their body is going to be a little bit more shocked. That is a spike in volume compared to what you’re normally used to.

The same thing with that big hike that’s untrained. Or let’s say, insert anything else that demands a little bit more from your body. Going to run for a 5 K when you haven’t really trained for a 5K and don’t really run a ton. You’re going to feel that 5K a whole lot compared to the person who’s been training and has that volume as normal. So that would be a spike in volume. Let’s say you did that back to back to back without recovery, you’re going to potentially cause something to start to hurt. That’s reaching our threshold of overloading and exceeding our capacity or our threshold in volume and the stress that we can handle. 

Now, let’s say you fracture something in that knee, you tore your ACL in, like the tibial plateau, and you’re non-weightbearing. Or let’s say that you are non-weightbearing because you’re a post-op and you had a meniscus repair. You started exercising a lot more on the uninjured side because you heard that that thing can get weak and you started training your upper body a lot. But let’s say you were just going crazy with the unoperated side. And you were doing single X sit to stands, you were doing all these different things, not really allowing yourself to rest, plus your non-weightbearing. So that leg is taking on way more of the load. It might not just be one moment, but it could be something where this is consecutive and not allowing yourself to rest or listen to the body that can cause this to reach that capacity threshold where it’s too much of a spike of volume. Your body’s not recovering from it. This could cause the uninjured side to hurt. Overcompensation from deficits like quad strength, and squat shifting, whether it’s going backwards towards your hips and your glutes and hamstrings, or maybe it’s to the unoperated side. That’s typically the biggest thing that I see is that people, when they try to get into that deeper squat position will try to shift onto the uninvolved side, and then that also causes that need to move forward. Not only is it that there’s more weight going through that leg, but they’re also punching the knee forward, not necessarily a bad thing. But if you accumulate that over time, that could create some patellofemoral pain on that front side knee of the uninvolved side. And that’s probably a pretty common thing that we can see.

We had an ACLer not too long ago come in and they came in with, yeah, patellofemoral pain on the uninvolved side as they were going through their rehab process somewhere else, and it’s because they were just compensating so much and doing so much on that uninvolved side. So that makes sense because they were just overloading and accumulating a lot of volume. The same thing can happen in running if there’s not an acclimation to maybe the steps per day or even a proper clearance of testing into a walk-to-run-type performance program. 

The next piece of this load management is intensity. Spikes in doing too high of intensity in the things that I mentioned can also do this. And it’s usually not a single blimp or point. However, it can happen if it’s way too much, and it really exceeds that threshold. It’s cumulative in nature and a lot of times based on one of these factors plus other daily life factors. I’ve mentioned in the past that life does not operate in these vacuums, so we have to co-exist with this ACL process. 

Let’s say you have a trip planned and you’re going on that trip, and there are a lot of steps and stairs for something that you’re doing. Work requires a lot of steps. Your physical job, or maybe you are a teacher or a nurse where you have to move around in a space and you’re accumulating maybe 8,000 to 15,000 to 20,000 steps in a day because you’re chasing six-year-olds around. And so this is just something important to consider because we usually won’t backtrack, what is it that I did in the past week or a few weeks that could’ve led me here? A lot of times it comes back to load management and understanding, okay, my body is trying to handle stress in my daily life, in my functional activities, daily activities, and I’m also trying to potentially work out and move. I need to balance that to ensure my body is recovering well and have good feedback loops to ensure nothing is exceeding its capacity. 

One other scenario that I want to share is basically when your compensations aren’t resolved, it continues to accumulate stress in these particular areas based on the movement which continues to trigger the problem. We see this all the time and when you look at different studies, it is very apparent that ACLers still will compensate even months to years out, whether that’s through running or movement, jumping, cutting, whatever that might be. There are plenty of people, especially if they don’t get the requisite movement and strength back. Then, therefore, their body is going to figure out other ways to do the thing, especially if you’re just kind of like, let’s say a year out and you’re just tired of rehab. 

You can run good enough. Your quad strength and your symmetry might be like 60%. Guess what, there’s going to be some compensations that potentially happen. And that’s just something that will occur in this process and it might not be as noticeable, it might be subtle, it might be less bending on the ACL side knee. But I guarantee you other areas like your patellofemoral joint are taking on more stress and your other uninjured side is going to be taking on more of that stress as well. This is just something that we see as well when these compensations from these areas that do not get resolved are problematic, but you continue to try to do the thing. And your body is just going to self-organize to do the thing. It might just do it differently. 

The last thing that I want to share here that I think most people would assume is that it needs to look perfect and consistent. And you need to feel the exact same thing every single time. And this goes back to motor learning principles and where it started. But basically, they looked at cobblers whenever they’re using their hammers. It’s actually interesting that every single movement looked similar, but the way that they activated different joints or movements actually was different. Each stroke might’ve looked exactly alike, but the way that they recruited different muscles or the way that they moved certain joints or moments actually had some variation to it. And part of that is by distributing stress to make sure there’s no overuse injuries. Our bodies are so skilled to be able to distribute stress that way. 

Now, this is different than someone who is not having the capacity or the movement range of motion to be able to get there, those movement options. And we first need to train those up isolated and then combined. And then create more movement solutions, if you will. And we want multiple solutions, just like the cobbler. The same thing with squatters we see really elite-level squatting athletes. You look at powerlifters or Olympic weightlifters, every single rep might look pristine and not too far off from what you would say is ideal. But the muscles, they’re recruiting can vary depending on each rep and the way they’re exerting themselves. But that is a very skilled motor control pattern. But it’s not because they’re compensating or there’s any issues anywhere. Their body has just become very efficient and it’s created a lot of options and solutions to be able to move, but still be very consistent in performance. This is something that is the goal for ACLers, but a lot of times it ends up being just one side or one area that is being avoided. So then other areas are picking up the slack. This leads to having those compensations and leading to stress increased. And increased in load, and then, therefore, it’s not managed as well. And then this ends up leading to pain on that uninjured side or other areas in the body. 

And many times when you go to clean up these movements and these compensations and do good rehab and work on strengthening. These things clean up and also the pain that you might be dealing with can also ease up as well. Because you now have created more movement options and especially the normal performance of that movement that is no longer distributing stress to areas that are unnecessary or overloading it too much. And this is where it comes back to having some really solid testing and assessments to know where you are, some planning and programming to make sure that there is an individualized plan and really good program design to build you up with where you’re at and those deficits to avoid any of those compensations that might come up.

And then also the support. You need to make sure that you have good guidance in this process and someone who is being that GPS for you because that is going to be so pertinent to avoid these types of problems. And a lot of times this is what we see, is that one of these areas is really lacking or multiple. And then for athletes to come to us down the road and deal with other side issues or deficits in the ACL rehab process, and it usually comes back to mismanaged programs or just general protocols. People are being pushed through random pain and stuff that they were supposed to be doing because the protocol says. Or because the PT didn’t have time to be able to adjust it or keep their eye on you. Or maybe it’s just something that got adopted because it never got addressed and you had a new compensation as your new normal. And that’s just kind of the way you’ve done it. Then that’s where a lot of this comes back to those pieces. But if you are someone who’s like, wow, my other side really hurts. This can explain a good chunk of what is going on in this process. In a nutshell, this is basically the principle behind it. I’m sure there are other exceptions to this, but I guarantee you this catches most of you guys. 

If you have any questions, of course, you can always reach out ravi@theaclathlete.com. You can catch me on Instagram ravipatel.dpt. You can go to our website, do a contact form, carrier pigeon, or whatever you want. We’re here for you. Thank you guys so much for listening. This is your host, Ravi Patel, signing off.

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