Hey everyone! This is Dr. David, of El Paso Manual Physical Therapy.

I’m going to talk to you all today about knee crepitus.

Crepitus is that crunchy sensation or sound that you might hear in someone’s joints. This is common in the knee.

Sometimes it happens in the spine, like in the neck or the back, hip joints, shoulder joints.

I have a kind of gruesome example for you guys. Turn up your sound. Make sure that you can hear this.

Warning, if you are easily grossed out by the body, this is one of the times where you might want to change the video or pause it or fast forward it or something.

You can’t see anything, you can just hear some really serious crepitus. Check it out.

Check out the video from 0:41 to 0:56.

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Gross, huh? It’s my friend, Edith.

Surprisingly this is not painful for her.

But I just wanted to explain to you guys how this works, why she’s getting that noise inside of her knee.

In the skeleton, the knee cap (patella) should be moving up and down on front of the thigh bone (femur).

There’s cartilage on the back of the knee cap and on the end of the thigh bone.That smooth cartilage should allow for some noiseless movements, some frictionless movement, or low friction movement.

What likely has happened in someone with some really bad crunchiness in their knee, the crepitus, is they’ve been wearing it down inappropriately.

The kneecap has the ability to move over to the sides and they’ve been wearing it down on one edge way more than they should.

Over time, the smooth cartilage can become rough.

Now in physical therapy school, we do cadaver dissections.

We look at the inside of deceased people for learning anatomy. and we’re looking at the inside of the joints and you could see the rough surfaces on the kneecaps and on the femur here, the thigh bone, and on this side as well.

Well on some of the cadavers, you can actually see the rough surfaces on the kneecaps and on the thigh bone and kneecap

You can see the spots where the cartilage is thinned out and grainy like sandpaper.

That’s why people only get crunchiness in certain ranges of motion because there are certain spots where the cartilage is rough and other spots where it is nice and smooth.

When that person bends the knee to the point where the joint rubs on the rough spot you hear that crunchiness. That’s why it happens.

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Now if it doesn’t hurt, you’re lucky.

But it’s only a matter of time before things might start to bother you.

If you get that crunchiness every time, it’s not a movement that you should be doing over and over.

I would certainly try to avoid it.

It’s your body telling you that there’s something wrong, and there’s something you need to do about it.

Here’s the good news for you:

Cartilage damage CAN heal.

It can restore itself.

Does it heal 100%?

That’s debatable, but it should be able to improve at least so that you can avoid having a surgery, taking pain medications and get back to being active.

It hurts me to see people let the knee problem go on to the point that arthritis develops and there’s a debilitating pain that is stopping them from walking or exercising.

…but you have to be doing the right things.

What I was explaining to Edith is that cartilage is a weight bearing structure.

It’s designed to take forces, especially at the knee.

When you put the wrong kinds of forces on cartilage, it responds in a negative way.

When you put the right kinds of forces, it’ll actually thicken and develop nicely so that you can put more and more forces on it.

It’s kind of like a callus.

I’ve got callus on my hands.

That’s an adaptation because I lift weights and my skin has thickened there so that when I go to lift weights again, it can better handle the weight that I’m putting on there.

But if my skin didn’t do that, then eventually my skin would tear.

If I put too much force on my hands way too fast it’ll tear as well.

It’ll blister, and then it might pop open and bleed depending on how bad it is. 

A similar process can happen at the knee.

There is too much inappropriate force going through the knee too fast and the cartilage doesn’t get a chance to thicken.

Instead of getting nice and thick and staying smooth so that the knee cartilage can take those forces, now it’s become rough and it’s noisy.

That’s why people get crepitus.

It’s the early signs of something more serious happening.

If you have this, please talk to us. You can instant message us, you can comment below if you want to know a little bit more.

You are welcome to call us at El Paso Manual Physical Therapy and set up a Discovery Visit where we can take a look at you and better tell you the exact cause of your crepitus. 

We want to get off pain medication, avoid surgery and keep up an active lifestyle.