Is it bad to pop your knuckles? Does it cause arthritis? I'm sure you've heard this.
I'm sure we all have heard that it causes arthritis at some point. But in order to answer this question, I think it's best we look at some of the anatomy of the hand. So you are looking at a dorsal aspect of a right human hand. Now I want to bring your focus to these right here.
These are called... metacarpophalangeal joints or MP joints because no one really wants to say metacarpophalangeal but beyond them we have what are called the interphalangeal joints or IP joints and these are examples of what are called diathrosis or synovial joints. These are the highly mobile joints in your body, right? If you can move it, chances are good that is a synovial joint. And synovial joints are the ones that pop or at least mostly pop.
There's different kinds of popping I should probably say this, right? There's an abnormal kind of popping that's more like tissue flipping and flopping all over the place, and we call that crepitus. That is a whole different story for another day, right? We're talking about just like your typical joint cracking, joint popping type sound.
So that's not really technically, I guess depends on who you ask, a crepitus. But that is going to be happening inside of synovial joints. So synovial joints are formed by what are called fibrous membranes or fibrous capsules on the outside.
So if we're looking at to this you can see a bunch of tendons and these tendons are traveling on the dorsal aspect of the hand and actually most of the tendons you're looking at are coming from the entire forearm right so the muscle belly is all the way up here in the form and then that turns into tendons traverses through the wrist over the hand and then it courses into the hand and goes towards like those distal uh bones of the fingers but there are some muscles inside of the hand itself it's just not very many but around those tendons you're going to see like this cloudy Look, that is connective tissue. And more specifically, it's what's called the fibrous membrane. The fibrous membrane is kind of like a ligament. In fact, some texts will call it the capsular ligament.
And what it's doing is it's connecting the bones of your hand. So deep inside of the dorsal aspect or palm of your hand is what are called metacarpal bones. And then in the digits, we have what are called phalanxes.
And so these phalanxes need to be connected to the metacarpal bones and that occurs with that capsular ligament or fibrous membrane. But just deep to that is a very thin piece of tissue called a synovial membrane. Synovial membranes.
are what produce synovial fluid, which is a lubricating fluid that has the consistency of egg whites. And what it does is it works with cartilage on either end of these bones here on the articulating surfaces of them, you're going to find what's called hyaline cartilage, which is very smooth and slippery, but you still want to have some kind of fluid to aid in that reduction of friction as a joint. Because I mean, if you think about how much... you can move your joints, that's a lot of friction or potential friction.
So you want to reduce that as much as possible. And so that's what the synovial fluid is there for. And this is an important player, or in fact the most important player, in terms of joint popping or cracking.
And that's because inside of this fluid we have dissolved gases, namely hydrogen, carbon dioxide, nitrogen, and oxygen. And what you have to understand is that when you actually change the volume, that joint capsule. So this is an enclosed space filled with fluid. Let's say I start to like push my hand in slightly different positions in that joint and what I'm doing is I'm actually changing the space inside and as I increase the volume of that space, I decrease the pressure and when you do that you create something what's called cavitation and this is where those dissolved gases rapidly form gas bubbles.
And here's the interesting part. It's the formation of the gas bubble that creates the sound. It's not the bursting of the bubbles.
We used to think it was the bursting of the bubbles, but it's actually the formation of those gas bubbles that creates that joint popping sound. So the question is, is that bad for you? And the short answer is actually no, there's zero evidence, or maybe not zero, but very little evidence to suggest that popping your joints is bad for you in the sense that the formation formation and even bursting of those bubbles is going to cause any harm and i should say that it takes around 15 to 20 minutes or so for those bubbles to actually burst some of them might burst during the knuckle popping you know extravaganza but most of them are actually going to take some time to actually break down and that's why it takes time for you to be able to pop your joints again because you need to be able to form the bubbles in the first place but do they actually cause damage to the joint it doesn't look like it um and there's been quite a few studies on this in fact we've even looked at this through an MRI in real time with people popping joints and it doesn't seem like there's really any damage occurring here but there's a really big caveat here because the position you have to put your joint in to achieve that pop could be damaging so when i was growing up my sister would pop her knuckles like this push them together and i thought it was so cool so i wanted to try and do that myself but i couldn't figure it out but i was able to pop my knuckles if i I pushed my hand back and then over time, I started to develop hypermobility in my hand and that's exactly what I have.
No one is going to argue that this is good for the hand. I am putting my joints in a really hyper extended position that they're not meant to have and that can cause damage right i'm stretching my skin i'm stretching tendons right i am stretching that capsular ligament or fibrous membrane and sure it does have elastic proteins inside of it but it doesn't mean it's there to be stretched as much as you want it to be stretched my point here is the position you put the joint in is extremely important so if you're out there you know like yanking on your neck and you get that pop you Right, if you're like me, here's another one. I don't know if I'm gonna be able to do it.
I don't know if you can hear that. Right there, my elbows are popping. The only reason that happened is because when I was a kid, I felt what I thought was pressure in my joints.
So I went up to my room, put my arm on my bedpost, placed my hand like this, and I just pushed. And I remember, this is real. I was sitting there screaming, I'm like, ah! And then it popped.
Again, I'm like six or seven years old. My elbow has never stopped popping since then. I think I compromised the joint. And now what happens is it very easily slips out of place somewhat, creating excess volume, causing cavities.
and you get those bubbles forming. That is bad. This is bad. So, and I think like popping your back, that's a whole video we're gonna have to discuss, right?
Chiropractics in general, because there's nuances there, because we're also looking at different joints in the back than just like your typical synovial joints, although there are synovial joints. So I think like generally speaking though, I think it's safe to say, That popping your joints isn't bad for you inherently. Nothing is wrong with the forming bubbles inside your joints, but the position you put yourself in to achieve it is very, very important. So do with that as you will.
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Thanks for hanging out with me for a little bit and I'll see you in the next video.