Episode 13 | Why Is Your Knee Swelling

What’s up everyone and welcome back to the ACL Athlete Podcast. So today is going to be interesting. I’m incredibly congested. Pollen is crazy around here, and I’ve sneezed at least 30 times. I’ve taken some Claritin, so hopefully that’s chilled out a little bit. But anyways, if I sneeze, I’m sorry. The other thing is that these houses, if you’ve been along the ride with me, there are these houses that are being built right next to where I record this, which is in my apartment, in my kitchen, and the houses are going up, they’re on the third floor and they’re moving pretty quickly, and they’re also deciding to cut their grass and blow the yard next to us.

So there’s a lot of stuff going on. So here we are. Today we’re talking about knee swelling in ACL rehab in your knee. So I wanna talk about what exactly it is, you know, when it happens, some of the things we use for it, as well as the feeling of it and what to potentially do about it. So let’s just go ahead and dive into it.

First, I just wanna make sure that, you know, this is purely educational. Every person is going to be very different. So consult your medical professional or healthcare provider for your specific case, cuz swelling can have a multitude of reasons as to why it’s coming up. And as we’ve talked about in previous podcast episodes, this is one of the four components of a quiet knee.

The other three that we talked about was quad activation, getting adequate range of motion, and then also minimal swelling. So what is swelling? Well, swelling sucks. No one likes it and it can delay a lot of progress. And I remember whenever I had my ACL injuries, and then the surgeries, and then even the rehab process.

It’s one of those things that if you’re going through this process, you know, swelling and you know sometimes why it comes up. And then there are so many times where you’re just like, why is this here? And you start to question like, what am I doing? The biggest thing you’ll question is like, is there something wrong with my knee?

And hopefully this podcast and this episode specifically can help shed some light on maybe some of those things that are going on and maybe to kind of game plan through. 

So let’s dive into it. So what exactly is swelling? It is also known as joint effusion. So that is increased intra articular fluid in the knee joint or any joint for that matter. That’s what joint effusion is. And here we’re talking about it specific to the knee. Sometimes you’ll hear some people say water in the knee as something referring to the swelling. So normal joints themselves. Roughly have around 3.5 milliliters of synovial fluid. Synovial fluid is just a fluid that’s within that knee joint.

When that volume increases greater than that 3.5 that leads to a effusion, which let’s keep this really simple here. It is just increased fluid or swelling in the joint. So when and why does it happen? This is the big question mark. Sometimes it’s very obvious, where it’s trauma. So you have an injury, so for this case, an ACL injury, there might be a meniscus or another ligament injury involved.

So that’s pretty straightforward. You know that there was something like trauma to the knee and that’s why the knee starts swelling because it is your body’s reaction to the injury. The same thing with surgery. Surgery is essentially trauma. You know, you’re going in there, you’re cutting, you’re sniping things away, and especially if you’re getting an ACL reconstruction, there’s tunnels that are drilled into your bones, and then you have a new graft there.

So it’s essentially like carpentry work to your knee joint. So that’s a lot of trauma, if you will, which is why the body needs healing time afterwards. Those are the things that are a little more straightforward. When there’s what we call a mechanism or we know that there was a specific instance where something abruptly changed, so that’s the injury or surgery or something like that.

Other reasons unrelated to these types of situations could be infection or some sort of global body thing that we’re not really going talk about in this episode. So we’re gonna keep it specific to ACL and knee injury related. Some other reasons could be related to load management, so you might be doing too much too soon or your body is not prepared for the activities that you’re doing, which is a very, very big piece of this that is especially important in ACL rehab.

Poor recovery goes along with this. Maybe it is pushing too much and not allowing your body to rest. And then tissue sensitivity, which is something where, as you’re going in this process, there might be some specific areas or specific, let’s say like cartilage or ligament, or maybe it’s a screw or something like that there, that could create some sensitivity that could cause the knee to flare up a little bit. 

So these are all things that can kind of play into this process and what makes it so difficult, that it’s not always so easy to know– what exercise did I do? Unless there’s that specific instance. There are different tests that can be done somewhere more in the medical office and are a bit more technical, but most of the time you can tell if there’s swelling in the knee.

And one of the tests that can be done is called the stroke test that you can kind of swipe on the inside of the knee and then see if any fluid moves when you go to the outside. Now, there’s a certain process for this that we’re not gonna necessarily talk about. It’s just something clinically that we will use and it can be graded from zero to three plus in terms of how the effusion is in the way that it moves.

Sometimes the knee is a three plus, which is the worst. There’s so much fluid that you can’t really move the fluid around. It’s just blown up like a balloon. So these tests can be helpful, but again, like most people who are experiencing swelling or joint effusion, it is pretty obvious and you can even visually see it.

Now, the things that you’ll feel, right? Everyone knows this. You’ll feel stiffness, you’ll feel some pain, some tenderness, potentially some warmth and some redness. I will get a lot of people who have difficulty bending and straightening their knee, especially trying to get full flexion of that knee and full terminal knee extension, which is very difficult because that knee has fluid in it and it throws off the mechanics and it’s not able to function as well.

The knee gets large and puffy. I see athletes all the time like this. What happens is they’ll describe a sensation where they’re really trying to flex it or bend it, and it feels like a lot of pressure at the knee, but it’s not very specific to a certain area. So those are some of the things that you might feel about it.

What to do about it is probably the most important thing here. Now, trying to figure out why it has happened will help you in this process. What I see mostly in ACL rehab in general is typically related to doing too much too soon. Maybe you’re on some sort of time progression and you’re at the fourth week and your physical therapist, or you feel like you should be at a certain point and you’re working through these exercises and maybe your knee’s just not ready to be there yet. And the thing that we have to respect, especially early on if there is trauma or if you have had the surgery, is that you have to respect the healing of the knee. Every person’s immune system and healing is going to be different. Some people I’ve seen, they lose their swelling really quickly and they never see it again. Sometimes they are dealing with it throughout the entire process, and this again goes back to you and also the procedure you had. Let’s say you had an ACL injury combined with an MCL and a meniscus– did you repair the meniscus? Did you cut the meniscus away? These things factor into it, so make sure you keep this in mind.

I typically see this when people are moving too fast and so they want to get to the next phase of training, and especially once they hit more impact related activities, so jumping, especially running, their bodies might not be prepared for it. That’s where these foundational pieces come in– making sure you get your range back, you get your quadriceps active and strong, making sure that you’re working on the swelling–all will help to mitigate a lot of these issues as you’re moving forward.

And this is where a very good rehab and program is going to be important to introduce you to this stuff in a very progressive way. It’s not just, okay, you hit the three month mark, you are ready to go. There should be drills of running mechanics and low impact that are building you up for these higher level activities. So that’s what’s most important. And if you feel like your knee is swelling or being reactive, you gotta take a step back. It’s one of these where you take one step back to take two steps forward, and it will make a huge difference because swelling will impact your progress. It will inevitably impact it. So make sure this is the first thing that you look at. 

Another thing that you can do is active recovery. So maybe your knee is swelling, you could do some light biking, something that is going to be very easy. Our muscles are active pumps for our bodies, so it helps to circulate fluid and blood. These are things that you can do to help with recovery and inflammation. Now again, this goes back to my last point: of is it because of  my training? So you gotta find the sweet spot there, and that’s where someone to guide you and help you with this process is important like your PT. 

Next up is elevation.

So this can be helpful, especially early on in the process when you can’t do as much. So this is raising your knee above the level of your heart and allowing gravity to help assist you in pushing some of that fluid out. Compression is another one that gets missed a lot, and I think it’s very important and it’s one that can really be a big game changer, especially if you’re consistently feeling compression.

Now, I know a knee sleeve isn’t super sexy, but like you can get a pretty cheap one on Amazon that is a compression sleeve that can really help with keeping fluid out of the knee and helping to push some out. Now, don’t go get a knee sleeve or a wrap that is going cut off your circulation. I’ve had some athletes where they’re like, yeah, I didn’t feel my foot the entire night. And I’m like, we don’t need that. So just find one that has a good amount of pressure that helps to support it and be able to keep some of the fluid out. But make sure you can feel your toes and you don’t have some funky numbness or tingling. 

And then the other thing that will come up is ice. Now ice is one of those that’s very interesting. There has been a lot of research on it related to inflammation and pain and swelling, and from what we know: It can help with pain. Does it slow down the healing process? That’s still kind of mixed. And then in terms of swelling, not really. So the thing that I would say about ice and what I advise most of my athletes is that if it feels good, great. Don’t go along thinking that you need it or that you need to ice it all the time. But I remember when I was going through this process, one of my favorite parts about this was the ice. I just got to chill and got some ice on my knee for about 15, 20 minutes, and that was a huge game changer and it made me feel good after putting it through all kinds of rehab and exercises. So this is one of those things that is more so up to you. 

At the end of the day with all of this. You know, we covered a lot. I don’t want you to freak out and think that it’s an infection or some sort of other weird thing. This is where having a good provider can really help you. So make sure that you talk to them about these concerns, and especially if your knee is swelling.

What is the game plan to address this? Is it to take a step back in your rehab to make sure we know what is going on and to control this? Is it to maybe get a compression sleeve or maybe it’s just kind of pushing through a little bit and it’ll go away. It’s really hard to say, but that is where hopefully this information can help you and allow the PT, who you’re working with, or a healthcare provider to be able to make a game plan to go forward.

The big takeaway here is the impact that it can have. It is really, really, really hard to progress your rehab and get to that end goal that you want, whether it’s returning to your sport or playing with your kids or going skiing. It is really difficult to get to those points if your knee constantly swells. It’s just not going to perform the way it needs to. The joint’s gonna move differently. The muscles are gonna be in protection and they won’t activate like they should. And so these are things just to think about and it’s gonna be hard to get back to the things like running and jumping and higher impact activities if your knee is constantly swelling.

So you gotta figure out the why, address it and have a game plan to go forward with and don’t feel discouraged if you have knee swelling. There’s not a single athlete that I’ve worked with, and even in my own experience of having to myself, that knee swelling didn’t come up. It’s just the body’s normal reaction, and if you were to do this anywhere else, it would swell up, but it’s very common with this type of injury. And it’s not uncommon to see it later in the process too. Just make sure that there’s something there to be able to attack it because it can be hard to make progress with it being there. 

So in review, joint swelling is accumulation of fluid in the knee. It can be caused by trauma, your training, maybe the recovery process and other reasons.

We can use tests such as a stroke test to see if there’s swelling and how much there is, and then it can feel stiff, puffy, painful. It can impact your range and the ability to activate certain muscles. You want to attack this by first adjusting your training and what you’re doing in rehab, making sure that you use some elevation or compression.

All of these things can be helpful in this process, and most importantly, the impact that this can have on your progress in ACL rehab. It’s very important, and I cannot stress this enough, it will be out of your control sometimes, but there is always something you can do about it. Just make sure you have someone that you are working with to be able to guide you on this process, because it’s super long, it’s super confusing. It can get very exhausting. So having someone from an accountability standpoint, and also just someone who’s guiding you, that way you can take the guesswork out of this.and make sure that you do have a plan in place to take care of swelling or anything else that comes up. 

All right guys. So that’s it for today. Thanks so much for listening and enduring my nasal congestion and all this building that’s going on. Just the perfect timing. But I appreciate you guys and thank you so much for listening. This is your host, Ravi Patel, signing off.