- What is that clicking, popping, snapping (aka crepitus) in your knee
- How common it is
- How to know if it’s a problem
- What you can do about it
What’s up guys, and welcome back to another episode on the ACL Athlete Podcast. Today is episode number 30. And we are talking about clicking, popping, all the things, all the noises in your knee today on this episode. But hold on real quick, listen to this… Now, go back and listen to that again, very closely, turn up the volume, listen to it. It’s not static in my mic, it’s my knees. That is the sound coming from my knees every time I go into extension and into flexion—that is crepitus. Crepitus is this technical term for this sound that a lot of people hear in different joints, whether that’s the popping, the creaking, snapping, or maybe the grittiness. Some people call it “rice crispies.” But the technical term is crepitus. Today, we are talking about just a lot of these noises, clicking, popping, whatever you want to name, that’s happening at the knee joint. And one of the most common questions I get, by far is, I hear this clicking in my knee, should I be worried about it? This podcast today is going to dive into that. So let’s get started.
First, I want to put out there a disclaimer that this is not medical advice, purely educational. If you have some issues here, go get some help, stop searching Google, stop getting on WebMD, and go actually get some professional help to get this figured out. Crepitus, clicking in the knee, this is all super, super, super common. I get this question a lot, especially from people when they’re on the ACL journey, whether that’s after the injury, maybe it’s like right around surgery, typically. There’s some swelling associated with the knee. They’re having pain. And it just kind of happens along in the process. But I’ve also seen this so much from just regular active athletes who are dealing with some aches or pains, or maybe they come in for something else and they want to get that checked out as well, to see, hey, is this an issue? Because if we hear that noise, it’s not always the most pleasant or flattering noise. Sometimes we get worried, am I doing harm by moving? Is this noise an indication of harm?
Well, the first thing that I want you to start off with is this general rule is noise does not equal harm or damage. Those things do not go together. And there is research that supports this that we’ll talk about here in a second. But it’s something that will help create some ease of mind as you’re going through this process, as you are processing if this clicking or weird sounds from your knee are a problem. And to answer the title of the question: clicking in your knee, should you be worried? The most typical answer you’ll hear is it depends. But the short answer, and for most of you on here is probably not. As I had mentioned, it’s very common. You just heard my knees and I don’t have any pain associated with the clicking or the crepitus that I have in my knees.
I have seen and evaluated a lot of different knees in different athletes, in ages, and even in different joints. About 95% of those people that I’ve assessed have some type of weird sound. It’s actually pretty abnormal to just not really have any noise in your knees if I’m going to be completely honest. In those 5%, maybe 10% of people who don’t are usually younger kids, or teens, and they’re still growing. And when I ask these people who have the sounds in their knees or they come to me and we assess it, the main thing I ask is, does this hurt or does it create any symptoms? And the majority of them will say, no. And that will help us know, okay, is this something that is an issue? Because I’m not going to say all noise in your knee is not an issue. There are some that can be. But this is where it’s important to figure out, okay, should I worry about it or not? And the majority of the time you shouldn’t. This is not a sign of joint damage or joint degeneration. As I had mentioned earlier, noise does not oftentimes equal harm or damage.
You’re probably wondering, well, what the heck is it? What’s making the noise? There’s something there. I know it, I feel it, I hear it. There can be different noises that can be attributed to different things, but let’s keep this super simple. One thing we’re going to talk about is cracking like a joint crack, almost like cracking your knuckles. People do this with their backs. And sometimes you’ll feel this in your shoulder or your knee. Sometimes it’ll open up some freedom or some range. This is one type of noise that you’ll feel typically it’s an instantaneous type of feeling, and this is called tribonucleation. It’s a fancy word for saying, we’ve got some gas bubbles in the joint. And because we are changing position or the joint position, that there’s a change in pressure that impacts those gas bubbles to create that noise. If you think about it, when you crack your knuckles like here. That’s not me cracking my knuckles out of place, I’m just creating pressure and changes in my knuckles that create gas bubbles that create the noise. That’s one piece.
Now, when you’re feeling this in your knee, typically it isn’t this instantaneous crack. It’s almost like this clicking, popping, creaking, snapping type feeling and this could be for a host of reasons. A lot of times it’s the joints getting into positions. Bones are moving on each other. Tendons a lot of the time are slipping around to create this movement from the muscles to the bones. And so a lot of times people will have this noise that is associated. They tested some of this stuff in research.
A study by McCoy in 1990, looked at crepitus in the knee. It found that 99% of people had some type of noise in their knees in the study that they had. De Oliveira in 2018, did a study where they looked at the sound and function in a group of women. The knee crepitus that they felt, the noise and their function, the worst pain that they had in months, and pain with climbing stairs and squatting, and this is with people with patellofemoral pain, there was no association between the sound and the pain that they were having. Even taking something like a group where they had knee pain and they looked at their sounds associated and there was no connection between them. A lot of times what I will see is that people will start to get knee pain and then they’ll start to associate the clicking with it. I felt this clicking and I think that’s why my knee hurts. But realistically [?] did a ton of jumping and that’s why your knee hurts. It’s not because of the clicking. Hello, correlation and causation; they’re not the same.
How do you know if these clicking, popping noises that you’re hearing in your knee are a problem? One question to ask yourself is, was there a traumatic accident that led to this clicking/popping noise that you’ve been hearing? So were you playing a sport? Did you fall? Was there a legitimate accident that could have led to something maybe clicking or popping? Then that is something that should be checked out. Usually, it’s accompanied by swelling, pain, or some sort of other signs that will tell you, you need to get this checked out by a professional. That’s one way to think about it.
If you did not have a traumatic issue, then the question is: Do you have a disorder of some sort, like Ehlers-Danlos syndrome where your connective tissue doesn’t stay in place and things can pop out of place. There’s a lot of tissue laxity. The majority of the time it is not Ehlers-Danlos. And people with this diagnosis are very, very, very small in the population. Now, this leaves us to the majority of you where it’s not a traumatic incident, it’s not something that you’ve been diagnosed with as a connective tissue issue. Anyways, if it’s not either of those two types of things, then you need to ask yourself with the sounds that you’re hearing and feeling, that clicking feeling, is that creating pain and is that creating swelling. Those are two things that will really give you a lot of information and will also help you to decide, you probably need to go and get this checked out. If not, then you’re probably good.
Most people will have these sounds and most people will not have pain associated with it. Also, if you notice that it gets better with exercise, it’s because our joints become more lubricated when we exercise. Think of it as a WD-40 on our joints. That’s why movement is so helpful. And the thing that we usually say is motion is lotion, so it helps things to glide better. You might not feel as much of that popping or clicking, the crepitus sensation that you have, and that’s because you have a better lubricated joint while you’re exercising. But then once things cool down, it might go back to that normal clicking/popping that you notice.
And one little caveat that I want to add for my ACL athletes. If you are someone who has had an ACL injury recently, if you had just had surgery or maybe you know you were doing your rehab or your training and your knee has blown up, and we’re talking about swelling specifically here, it is not uncommon for that swelling to really impact the way that the different bones and tendons and ligaments move together. Because if you think about fluid in the joint, if it’s increased, then even the surface between your kneecap and where your femur, which is your thigh bone, and your tibia, which is your shin bone, all those connections there will be increased space there. And it depends on where the fluid’s hanging out. And then we got to think about the tendons and the fascia and the ligaments, all that stuff in the knee space. If you have fluid in there, then that is throwing off some of those mechanics of how those joints move. Is that bad? Not necessarily, unless you just don’t get rid of the swelling.
That’s why swelling just sucks and it’s something that we need to work through. And it’s something that I’ve done a different podcast episode on. But just know if you’re going through this process, that if there’s joint swelling, it’s not weird for you to feel some weird clicks or pops. Hopefully, that will change as your knee starts to calm down and get to its normal joint mechanics. And as long as it’s not associated with that pain or continuing to keep that swelling there, then we’re on the right track.
If you have noise in your knee, and it is specifically causing pain or swelling, then you should get it checked out with a medical professional. The important distinction here is that noise causes pain or swelling, you can have both. Just like that study that I mentioned they have patellofemoral pain and they have clicking, but they were not associated together. The same thing here, you need to make sure that every time my knee clicks, it is very obvious that this is causing some direct pain or swelling, then you have to get it checked out. If you have noise in your knee and it is not creating any pain or swelling or limiting you from moving, then carry on.
Big takeaways here: Noise in your knee does not equal damage or harm. It is incredibly common to hear this stuff in your knees. You heard mine, so just know you’re not the only one. If you have concerns about it, then ask yourself, is it a traumatic accident that this is resulting from? Is it something where I have been diagnosed with something where things are very loose and coming out of joint or places a lot of the time? Again, a very low percentage of people have this type of issue or disorder. And then, is this noise directly causing the pain and swelling, and symptoms that I’m experiencing in my knee? So when in doubt, get it checked out. I got a lot of rhymes today. Sorry, not sorry. But this also means do not go to Dr. Google or WebMD, or ask Joe on Instagram. Go to someone who is qualified and who you can trust to give you the right information.
All right, good. So that’s it for today, guys. If you want to come on here, talk about clicking in the knee. I get the question so much. And I hope that this helps and it helps to put some anxiety or questions at ease. And as always, if you do have questions, please feel free to reach out at email@example.com or on Instagram at ravipatel.dpt, and slide into the DMs. Do you feel me? All right, guys, till next time. This is your host, Ravi Patel, signing on.
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