Whether you just have knee popping sounds without pain or if you have a knee that pops out of place, watch the video to learn how to stop knee popping and pain.
What Are The Causes Of A Knee That Pops?
If you have a knee that pops you may wonder what causes it and if it's a sign of something serious.
The good news is that you don't need to worry too much if your knees are popping. Popping knees are rarely a serious problem.
However, knee popping is a sign that things aren't moving ideally, and it's a warning sign to pay attention. Poor movement patterns left untreated for long periods of time can lead to bigger problems over time such as degeneration of the cartilage in your knees which can lead to knee arthritis.
There are two main categories of knee popping:
- Popping inside the knee joint
- Popping outside the knee joint
(Plus, a middle category which I'll explain later.)
Internal Knee Joint Popping
By internal knee joint popping, I mean popping inside the joint between the lower leg (tibia) and the upper leg (femur).
If you have something inside of that joint that's grinding, for example a torn meniscus or knee arthritis, it can cause popping sounds.
With a torn meniscus, you might even get a locking where, your knee won't move. That can be really scary, and if your knee locks a lot, it might be a bigger problem.
However, if you're just getting popping sounds and you're not getting locking and you're not getting any knee pain, then it's probably not a really big deal.
Now, if you are getting pain from your knee and you're getting some popping or clicking or grinding sounds from deep inside the knee joint, there's a chance you may have some knee arthritis.
However, just having knee arthritis doesn't mean you'll have knee pain.
In fact, in people over the age of 40 without knee pain, 19-43% demonstrate findings of arthritis on an MRI according to a study in the British Journal of Sports Medicine.
What Causes Popping Inside The Knee Joint?
Twisting between the upper and lower leg bones (femur and tibia) is the primary cause of popping inside the knee joint.
Whether the popping is coming from a meniscus problem or knee arthritis, it's the twisting between the two joint surfaces that creates the popping or grinding sound. If the twisting continues over time, eventually it can cause inflammation and pain.
Causes Of External Knee Popping
Sources from outside of the knee joint are the more common cause of knee popping.
Popping outside of the knee joint can be caused by poor tracking of the kneecap, or by IT band syndrome.
Your IT band is a long band of fascia (kind of like a tendon) runs along the outside of your leg.
The IT band passes over the outside of the hip and then runs down the leg over the outside of knee.
As you bend and straighten your knee, the IT band rolls over the outside of the knee at around 30 degrees of knee bending. Therefore, if you get popping every time your knee bends and straightens, it's likely the IT band that's at fault.
Pain on the outside of the knee from the IT band is sometimes referred to as Runner's Knee, because runners repeatedly bend and straighten their knee for miles and miles on end for days, weeks, months, and years on end.
Poor Kneecap Tracking
The IT band also has fibers that attach into the outside of the kneecap.
When the IT band is stiff, it can pull the kneecap toward the outside of the knee, which is an other source of knee popping.
The kneecap normally runs up and down in a groove on your thigh bone as you bend and straighten your knee.
If it's right in the center of that Groove there's usually not any sound that's associated with it. However, if the knee is off to the side of the groove, it can rub against the outer edge of the groove and create a popping sound as well as knee pain.
This is particularly true if you have particularly if you have weight on your leg such as when going and down stairs.
A Third Cause Of A Knee That Pops?
There's an intermediate category of knee popping that's not quite inside and not quite outside the joint.
That type of knee popping is from the joint between the kneecap and the thigh bone (femur). Excessive compression of the kneecap on the femur can cause a mild form a kneecap arthritis called chondromalacia patella.
When the cartilage behind the kneecap wears down, it can cause a popping sound when squatting or going down stairs.
How To Stop Knee Popping And Pain
Essentially, you want to limit the amount of twisting and rotation between the tibia and the femur.
The knee is primarily a hinge joint that shoulder move straight forward and backward, but it does have slight amounts of side-to-side and twisting motion.
When your foot is planted on the ground that side bending and twisting are coupled together. You can see that from the picture below.
As you can see from the left-hand side of the picture, when the foot flattens (or prontates), it can causes the knee to bend and twist inward. This in turn can cause knee popping and grinding.
So How Do You Prevent Knee Popping?
Surprisingly, preventing knee popping has vey little to do with your actual knee joint.
It has more to do with the strength in your hip muscles. Your hips are the part of your body that controls the rotation of your leg, and thus the position of your knee.
Thus, in order to prevent knee popping an knee pain, you want to strengthen your hip abductor and hip exenal rotator muscles.
Examples of exercises to prevent knee popping and pain include:
Balancing on one leg
The best functional exercises you can do is just standing on one leg. Try to balance without a lot of twisting or side to side movement.
You may have to hold on to something if you're just starting but you want to where you can balance pretty well without holding on.
Exercise For A Knee That Pops Going Up And Down Stairs
If you get popping going up and downstairs then the next step would be to do little knee bends while still trying keep your knee from going side to side.
This helps strengthen your gluteal muscles while also improving your balance.
Learn more about how to stop knee pain going up and down stairs here.
What Other Exercises Can Help A Knee That Pops?
Another big factor in controlling the side-to-side motion of the knee is improving stiffness in the ankle joint and calf muscles.
Why is that?
If you take a step you need to be able to move your body weight over your foot.
If you have a stiff calf muscle a stiff ankle joint you're not able to do that.
Therefore, your body needs to be able to get where it's going, so it finds alternate Pathways around the ankle.
The most common pathway that people find to compensate is to pronate, or flatten their foot.
That causes your knee to go inward and can cause your knee to pop.
Therefore, stretching your calf muscles is a really good thing to do if you have a knee that pops.
Most people have at one point seen how to stretch their calves either in gym class or playing sports when growing up.
However, most people make some critical mistakes when stretching their calves.
Learn how to stretch your calves correctly.
Need Help For Popping Knees?
Request an appointment with one of our specialist physical therapists.
Knee That Pops Out Of Place?
Some people have a really shallow groove or they've torn a ligament that normally helps hold the knee cap centered in the groove on femur.
If that's the case occasionally people will get a kneecap that pops out of place.
When the knee pops out of place, it can be incredibly painful.
Sometimes it just pops right back in. Other times, it actually stays out and you kind of have to pop it back in manually (or have someone else do it).
When the knee pops out of place, it can cause you knee to feel locked up and unstable.
How To Stop A Knee That Pops In And Out Of Place
Just as mentioned above, and it's really important again to maintain that neutral alignment of your hip as mentioned earlier.
That keeps the the femur from going inward while the kneecap goes outward.
So the same exercises like balancing on one leg and doing little knee bends applies.
However, sometimes if your knee pops out of place you need a little bit of extra help to improve the stability of the kneecap.
Do Braces Help A Knee That Pops Out Of Place?
There are some knee brace that braces that can help a knee that pops out of place. These kind of braces should hold the kneecap centered in the groove of the femur.
The BraceAbility patellar knee brace is good for people with a knee that pops out of place. The C-shaped pad in the picture helps hold the kneecap in the proper position.
(Note: While I really like this brace, the picture above from amazon actually shows the brace on upside down. The C-shaped pad should go on the outside of the knee.)
Can Orthotics Help If Your Knees Are Popping?
If your feet overpronate, orthotics can also help keep your knees from going inward an help prevent popping knees.
If you're not having any pain when your knees pop, you may just need an over-the-counter insoles.
i would recommend Superfeet green insoles for people with low-to-moderate height arches.
Or if you have high arches, Spenco high-arch insoles help better absorb shock while supporting a high arch.
Or, if your knee popping is painful, you may need a custom orthotic. If you're in the St. Louis area, we'd be happy to fit you for custom orthotics.
Need More Help For Knee Pain?
If you try the tips in this post and you're still having knee popping and pain, tap the button below to request an appointment with one of our specialists to learn how we can help.