Why Do My Knees Crack When I Bend Them

Symptoms & Signs Of Crepitus

Crepitus, or joint sounds, can be a normal part of movement. Many people experience popping joints, especially as they get older. You may notice:

• Popping or cracking when you bend your knee or elbow
• Crunching sounds in your knee when you go up or down stairs or kneel
• Crackling or grinding sounds or a crunching sensation when you move your shoulder
• Occasional or continual swelling around the joint

Joint Popping Symptoms & Treatment

In orthopedic medicine and sports medicine, crepitus describes a popping, clicking or crackling sound in a joint. Joint popping sounds may mean that air is moving in the joint, which is usually harmless.

People most often notice crepitus in their knees, but it can also happen in other joints like the shoulder, elbow or neck.

Crepitus with pain can be a sign of wear and tear or injury. If crepitus is painful, you should consult a doctor.

At Aurora Health Care, we offer a range of treatment options for crepitus from noninvasive therapies like bracing to the latest in minimally invasive surgical techniques.

Knee Noise: Crepitus And Popping Explained

You may hear occasional pops, snaps, and crackles when you bend or straighten your knees, or when you walk or go up or down stairs.

Doctors call this crackling sound crepitus .

One explanation for why this happens is osteoarthritis, but there are many other causes. In most cases, noisy knees arent a problem. However, if you have pain, too, you might want to consider asking a doctor to check out your knees.

Crepitus in the knees is different from crepitus or crackling in the lungs, which can be a sign of a respiratory problem.

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My Knees Crackle When I Bend Them

It also affects weight-bearing joints such as the knees and hips. Mechanical stress or biochemical changes slowly break down the cartilage that cushions the joint, causing inflammation and pain. Over time, the cartilage is destroyed and the bones grind together. When crepitus is accompanied by pain, its usually caused by OA. Crepitus in the knees may be caused by knee injuries such as.

These are fairly common in people who play sports, jog, or run. A meniscus tear can cause crepitus as the joint moves.

Is a dull ache behind the kneecap, usually caused by overuse or injury. There will be damage to the undersurface cartilage covering the kneecap., or runners knee, is caused by a force overload on the patella that occurs before theres actual damage to the joint surface of the patella. This syndrome can lead to chondromalacia patella. If you have chondromalacia patella, youll feel and hear a painful crunching and grating when you move your knee. Other and types of arthritis can also cause crepitus. And treatments for joint pain are available at drugstores, health food stores, and online.

Why Do My Knees Click

There are 2 main reasons for getting kneecap noises its either from bubbles of gas popping or the kneecap not tracking in the knee joint groove properly. Gas Bubbles: Sometimes tiny air bubbles build up within the fluid inside your joints. These bubbles make a noise when they burst during joint movement.

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Things Your Knees Are Telling You If They Crack Or Pop

If you notice that your knees make cracking or popping sounds when you bend, it can cause a bit of concern. But according to experts, there may not be any reason to worry. Those cracking sounds are completely normal.

“Our bodies are made to move and things that move make noise,” Dr. Austin Misiura, DPT, owner of Pure Physical Therapy, tells Bustle. “As we use our body tiny irregularities can form. For example, if you get a deep cut, you likely develop a scar which is slightly darker and thicker than the surrounding skin. The same happens if we injure a tissue that we canât see, like a tendon or ligament.” Scars, for the most part, aren’t bad. If the tissue surface is not completely smooth, it may “click” as you use it.

The cracking, snapping, and popping can become more noticeable with age. But it can happen to anyone. According to Dr. Misiura, there are a few different reasons why knees, or any joint for that matter, makes noise. “Most of them are not necessarily a bad thing,” he says. “This isnât to be thought of the same way as when your car makes a noise.”

So a good rule of thumb is, if there’s no pain, you’re likely OK. But here are some things it can mean if your knees crack or pop, according to experts.

Gas Bubbles In The Synovial Fluid

This is the most common cause of knee cracking and is normal and happens to everyone of all ages. Over time, the gas bubbles form inside the synovial fluid that surrounds the joints. So, when you’re squatting and bending your leg, some of these bubbles burst, creating a popping sensation or an audible “crack.” Crepitus caused by the formation of gas bubbles does not cause pain, and do not worry about it.

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Why Do Your Knees Click And Should You Worry

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At Complete we see thousands of knee complaints every year, from an 80 year old gentleman with osteoarthritis to a 23 year old professional footballer following ACL reconstruction.

One of the most common questions we get in clinics is why does my knee click? So, if you have clicky knees you are certainly not alone!

Often the question is phrased slightly differently and patients relate it to certain activities, such as.

Why do my knees click when I walk?Why do my knees click when I squat?Why do my knees click when I go upstairs?Why do my knees click when I go downstairs?

Next our clinicians would enquire is the clicking painful? If the answer is no then the simple answer is no it does not matter.

Joints make a variety of noises, patients describe

popping, snapping, cracking, catching, grinding, grating and clunking!

The medical term we use for clicking is crepitus, from the Latin meaning to rattle. It is not just old people that experience it, can affect people of all ages!

The video below is Helen OLeary our clinical director of Complete Pilates. She is a fit and active 34 year old with very clicky and clunky knees .

She has never injured her knees it does not stop her running or playing sport and she has never had any knee pain. Is she worried now or about the future of her knees?? No not at all!

Common Questions About Knee Popping

1. Will Knee Popping Go Away?

In most cases, knee pain and popping will settle down, but how long this takes will depend on what is causing the popping noise. Soft tissue injuries usually heal in 6-12 weeks. Most people notice their knee popping settles down within 3 months of working on knee strengthening exercises.

If there is no pain with the popping, then it is highly likely the popping noises will continue as there isn’t a mechanical problem to be fixed. Bit rest assured, there is no increased risk of knee problems later in life.

2. Is Knee Popping Bad

In most cases, knee popping is not a serious problem, it is simply bubbles of gas popping, or tendons snapping over small, bony lumps.

However, knee popping can be serious if there is a sudden popping noise from the knee at the time of injury, which typically indicates a significant injury to one of the knee ligaments.

3. Why Do Knees Crack When Squatting?

Many people complain of popping, cracking, or crunching noises when they squat down. The technical term for this is cavitation or crepitus, which simply put means “joint noise”. Caused by a change in pressure inside a joint, gas bubbles of carbon dioxide form, and when they burst, you get the familiar cracking sound in your knee.

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4. How Do I Crack My Knee Safely?

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What To Do If The Knees Click When You Bend Or Straighten Them

If the knee clicking is not causing any pain or hindrance in daily movements, then it is not a cause for concern. It the patient has difficulty in moving and also has other symptoms such as pain and swelling in the knee joint, then it is important to seek medical attention immediately. Treatment will depend on the cause of the knee clicking and includes: rest, medicines, exercises physical therapy etc.

The Gas Inside Your Joints Are Popping Back Into Place

This is less common with knees, but it does occur. Cavitation is the “official word” for what happens when you crack your knuckles or when someone cracks your back. While Dr. Misiura says the exact mechanism is still a little fuzzy, “it is thought that the sound comes from the gas inside the joint ‘popping’ back into the middle after the tissues have been stretched slightly passed their end range.” According to him, it’s almost like a depressurization when you pop your ears on an airplane. If there are no painful symptoms involved, you don’t have to worry.

Read Also: Why Do My Knees Crack When I Squat

Meniscus Tear Not Everyone Needs Surgery

For people 50 years old or older, a torn meniscus is very common. Its also a very common injury for competitive athletes. The good news is that some meniscus tears can heal by themselves. In the past, doctors frequently recommended surgery for meniscus tears. However, new research shows that surgery probably does not provide many benefits in the majority of cases. In fact, your risk for needing a future knee replacement may increase if you have meniscus surgery.

If you have had an injury, however, surgery might still be an option. In these cases, the tear may occur in fresh, healthy tissue, which is much different than a gradual breakdown over time. Also, the level of pain might determine if you should have meniscus surgery. The procedure may involve sewing together the torn meniscus or snipping off pieces of cartilage getting stuck between bones.

In most cases, a conservative approach works best for meniscus tears. This may include rest, physical therapy and anti-inflammatory medications.

Why Do My Knees Crack

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UABs Harsvardhan Singh, Ph.D., says typically, there is no concern if there is no pain associated with knee cracks.You might have heard this sound before: the loud pop or crack of someone elses or your own knees. Sometimes it can be an unpleasant experience, but one researcher at the University of Alabama at Birmingham says typically, there is no need for concern.

What does it mean that my knees crack?

Knee cracking could mean lots of things, said Harshvardhan Singh, Ph.D., assistant professor with UABs Department of Physical Therapy. If it is painful, then you should see a health care provider.

Singh adds that a painless knee crack could come from multiple sources:

• A large-sized kneecap that does not fit well into the groove, thus producing a cracking sound during activities such as running and jogging.
• If the thigh muscle is too tight, it can pull the kneecap and affect its free gliding movement, generating a knee crack.
• If the various soft tissues such as cartilage or meniscus have degenerated, resulting in loss of smooth cover of the knee joint, and leading to knee cracks during various activities.

The degenerative changes can also lead to pain and/or locking of the knee joint, he said. Typically, degenerative changes are common in older people, so a degenerative change-associated knee crack may be found commonly in older people.

Should I be worried if my knees crack often or loudly?

Harshvardhan Singh, Ph.D.Does this mean I have arthritis?

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Knee Popping By Activity

Knee Popping When Extending: Knee popping when you straighten your knee is usually due to gas bubbles , plica syndrome or patellofemoral pain syndrome.

Knee Popping and Pain When Bending: If you get knee popping and pain when bending your knee e.g. squatting down, it is most likely due to a problem with the knee cartilage such as a meniscus tear or chondromalacia patella.

Knee Popping When Extending And Bending: If you get knee pain and popping with both knee flexion and extension, it is likely that there is damage to the joint surface such as cartilage damage or knee arthritis. If there is no pain, it is likely to be gas bubbles popping.

Knee Popping With Twisting: Sudden knee pain and popping when you twist is usually doe to a knee ligament injury, most often an ACL injury and/or MCL tear. If the knee swells up or feels unstable after hearing a pop as you twisted, seek medical attention immediately.

Knee Popping When Walking: Almost all the possible causes of knee popping that we’ve looked at here can cause knee pain and popping when walking, be it arthritis, runners knee, cartilage tear or ligament injury. There will usually be other symptoms associated here that will lead to a clearer knee pain diagnosis.

Cartilage Injury Or Wear

In an injury, knee cartilage can break off and catch on the joint, which causes pain and swelling.

Or, the cartilage may wear down from arthritis, which leads to a painful grinding feeling during movement.

If youre concerned that either of these causes could have led to painful or swollen cracking knees, find a clinic near you and book a physiotherapy assessment today.

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Other Tips For Dealing With Cracking Knees

Heres some advice to maximize your knee health and stability:

• Practice non-impact knee strengthening exercises like cycling, spinning, water aerobics or swimming
• If you have pain after workouts, apply cold for 15 to 20 minutes to each knee. Try a bag of ice wrapped in a damp towel
• Dont squat for long periods or sit in uncomfortable positions get up and move around frequently, for example, during long plane rides.
• Make sure you use well-fitting footwear avoid walking in bare feet or on uneven surfaces
• Consult with a physical therapist about knee strengthening exercises you can do at home
• Keep your weight under control to put less strain on your knees avoid carrying heavy loads, especially up and down stairs

What Are Some Of The Causes Of Knee Cracking

Now we go into the details of what actually produces the cracking sound with any movement of the knee. For this, we need to first understand about a fluid which is present in the body called the synovial fluid. This fluid is present between the joints in the body and acts as a lubricant or shock absorber. This synovial fluid is present in the synovial membrane which encompasses the end of our bones.

The synovial fluid prevents the bone from rubbing against each other such that there is increased friction between bones which may lead to degeneration of the bones, a condition called as arthritis.

Coming to the cracking sound, when we move a tight or stiff knee, the space between the bones gets expanded which results in a gap being created between the bones where synovial fluid rushes in to fill the gap.1 The movement of the synovial fluid in this gap is what that produces cracking Sound.

There are certain other causes for Knee Cracking as well and these are:

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Knee Popping With An Injury

Was there is a loud “pop” as you twisted or bent your knee? Knee popping pain at the time of injury usually indicates damage to one of the ligaments.

The two most common ligament injuries that produce knee pain and popping are ACL and MCL injuries, usually caused by twisting the knee awkwardly.

ACL Injury

What is It? The ACL gets over-stretched and tears, either fully or partially. Sudden knee pain and popping at the time of injury usually indicates a complete tear of the ACL

How Does It Happen? The ACL typically gets damaged when there is a hard blow to the side of the knee , sudden twisting or deceleration, or when the leg bends backwards too far

Symptoms? Approximately 50% of ACL tears are accompanied by a popping sound at the knee associated with immediate swelling and pain. The other classic sign of an ACL tear is the knee repeatedly giving way. The knee pain and popping usually only occurs at the time of the injury, there isn’t typically any recurrent knee clicking or popping afterwards

Treatment? ACL Injury treatment will depend on the extent of the tear but usually involves exercises, knee braces and/or surgery

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MCL Injury

What is It? The Medial Collateral Ligament on the inner side of the knee gets over-stretched and tears

How Does it Happen? The MCL usually gets torn when a force gores through the outside of the knee e.g. tackle, or sudden twisting e.g. skiing

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My Knee Popped Should I Be Worried

The vast majority of people with grinding or popping in their knees do not have pain and most do not need to worry. But some have had new or older injuries and now your knee pops. There are three basic groups we see who complain of their knee making a popping sound.

Now, there are those of you who might have painful snapping or popping in your knee. Lets explore some of the more common reasons for painful knee clicking, popping, and snapping.

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