Knee Clicking and Cracking: When It Is Harmless and When It Is Not
Many people hear their knees click, crack or pop when they stand up from a chair, climb the stairs or squat down. The sound can be surprising, and many people start to worry straight away. In most cases, a noisy knee is simply a noisy knee. This article explains where the sounds come from, when they are usually harmless and which signs mean it is time to talk to a doctor.
Where do the sounds come from?
The knee is a busy joint. The thigh bone, the shin bone and the kneecap meet there, and many tendons and ligaments run around it. Doctors sometimes call joint noises crepitus. There are several common explanations:
- tiny gas bubbles in the joint fluid that are released when the joint moves, much like cracking your knuckles,
- a tendon or ligament sliding over a small bump of bone and snapping back into place,
- the kneecap moving in its groove when the muscles around it are tight or unevenly strong,
- cartilage surfaces that are no longer completely smooth, which can cause a soft grinding or crunching feeling.
The sound alone does not tell you which of these is behind it. What matters much more is how your knee feels.
When clicking is usually harmless
A click or a crack is usually nothing to worry about if:
- it does not hurt,
- the knee is not swollen,
- you can bend and straighten the knee fully,
- the knee feels stable and does not give way.
Many people with completely healthy knees have joints that click every day. A single pop after sitting for a long time, which disappears after a few steps, is very common.
When you should pay closer attention
Noise is a reason to see a doctor or a physiotherapist when it comes together with other signs, for example:
- pain that comes with the clicking or gets worse over time,
- swelling, warmth or redness around the knee,
- a knee that catches or locks and will not straighten fully,
- a feeling that the knee gives way under you,
- a loud pop during a fall, a twist or a sports injury, followed by pain or swelling.
Signs like these can point to a meniscus problem, irritation behind the kneecap or wear of the cartilage. Only an examination can show what is behind them. Our article on when knee pain is serious lists more warning signs.
Grinding: a different kind of noise
A soft, rough grinding, especially when you climb stairs or rise from a squat, is common in people with worn cartilage under the kneecap or in the joint. It does not always hurt, but if it comes with stiffness or pain, it is worth having it checked. You can read more in our article on knee cartilage wear.
What can help a noisy knee
You cannot always make the sound go away, but you can often make the knee feel more comfortable:
- keep the muscles around the knee strong, especially the front of the thigh and the hips,
- gently stretch tight muscles, for example the front and back of the thigh,
- warm up for a few minutes before exercise instead of starting cold,
- change position often if you sit for a long time,
- keep the knee warm on cold days, because many people feel stiffer in the cold.
Simple strengthening exercises at home are a good place to start. If an exercise causes pain, stop and ask a physiotherapist for advice.
Can a knee sleeve help?
A knee sleeve will not stop the clicking, and it does not repair cartilage. What it can do is give the knee gentle, even compression, warmth and a feeling of support. Many people say this helps them feel more confident on stairs, on walks and in everyday activities. A soft bamboo sleeve can be worn under clothing during the day without anyone noticing.
Frequently asked questions
Why do my knees crack when I squat?
Most often because of gas bubbles or tendons sliding over the bone. If there is no pain, swelling or locking, it is usually nothing to worry about. If squatting hurts or the sound started after an injury, have a doctor examine the knee.
Does knee clicking mean arthritis?
Not necessarily. Clicking is common in healthy knees too. Grinding that comes with stiffness or pain can be linked to cartilage wear, but only a doctor can assess that.
Can exercise reduce knee clicking?
Sometimes the sound becomes less noticeable when the muscles around the knee are stronger and more flexible, but not always. Exercise is worth it anyway, because it helps the knee feel more stable.
A sleeve you will actually wear
The best sleeve is the one that does not end up in a drawer. The KeenTrove Bamboo Knee Sleeve is made for exactly that:
- soft, breathable bamboo, comfortable even in summer
- fits snugly but does not dig in behind the knee
- does not lock the knee, so you move naturally
- wear it under your clothes during the day and in bed at night
With 60 days to get your money back, you have nothing to lose.
Note: this article is for information only and does not replace an examination by a doctor. If you have circulation problems or diabetes, or have recently had knee surgery, talk to your doctor before wearing compression.
