Snap, click, click, cluck... Some people's knees "talk a lot".
These loud noises usually occur when the knee is flexed and extended, such as squatting and standing up, walking, or going up and down stairs. In most cases, the knee joint sound is physiological, does not mean that there is a disease, but only an innocuous "broken thought".
But there are also parts of the noise that are pathological, and the knee "scolding and grinning" is urging you to go to the examination and treatment early, so as not to cause more serious damage.
How to tell what the knee is saying requires you to listen to it like this:
Listening to a single sound is not enough
To say that listening to a "click", you can immediately determine whether there is a disease and what is a disease, the current technology can not do it. However, the characteristics of the ringing can give us some tips to help us initially determine whether there is a serious problem behind the knee ring.
Remember when your knees started ringing, can't you remember? That's fine. Physiological noises are usually not impressive, and the time of the beginning is not remembered. Pathological ringing often begins with an injury, and the first ringing scene is often unforgettable, such as many people with broken knee ligaments who remember the loud sound at that time.
In addition, physiological sounds usually appear by chance, and after just ringing, the repetitive movements will not ring again, there is no specific induced posture (not if you want it to ring, it must be sounded), and the sound does not gradually become louder or more frequent. If the frequency of the sound increases, even every time a certain posture is made, the sound is more likely to be pathological.
Figure | pixabay
"Snap" – the knees that are not sick will also ring
Compared with the knee ring, everyone is more familiar with the sound of breaking the fingers. Pulling or pressing the finger hard, the joint may make a crisp "pop", but pressing the same joint again for a short time will not make a sound.
A similar noise occurs in the knees, which comes from small bubbles inside the joint fluid. Scientists believe that when the joint is flexed and extended, the pressure in the joint cavity changes, and the sudden formation or rupture of the cavitation will make a noise.
One study performed an MRI examination while pulling a subject's finger丨Reference[2]
Studies have found that the formation of vacuoles in the lumen of the finger joints occurs at the same time as the sound丨 References[2]
The sound of this bubble does not cause pain by itself, and researchers have tried to break their fingers twice a day, each time only breaking the left hand without touching the right hand. After breaking more than 40,000 times in 60 years, he found that there was no difference in the joints of the two hands, and he won the Funny Nobel Prize for it (of course, it is still not recommended to break hard, after all, some people have broken bones because of this).
When receiving the award, researcher Donald L. Unger shouted to the mother who opposed the finger breaking: I know you can hear, Mom, you | are wrong! 2009 Ig Nobel Prizes
"Cluck" – not seriously ill, but be careful
Sometimes, the sound is not so crisp, but "clucking" like plucking a string, and the hand can feel the vibration when you touch your knee.
This type of sound may come from friction between tissues such as tendons around the knee and bones, such as during knee flexion, the lateral iliotibial band of the knee is blocked by a small bulge on the outside of the thigh femur, and as the angle of the knee flex increases, the iliotibial band is pulled tighter until it suddenly slides over the bump and bounces back to its original position to make a "clucking" sound.
During knee flexion and extension, the iliotibial band slides over the lateral epicondyle of the femur | Prof. Bellemans
In addition, friction between other tissues, synovial or physiological folds, meniscus hyperactivity, etc., may also make noise during activity.
If there is no pain and no significant damage to the tissues, this type of sound cannot be strictly counted as "sick". However, if the knee continues to ring, the situation may suddenly worsen with increased exercise or under a certain movement, and the pain will appear.
When the sound comes from an imbalance in the muscle strength of the lower extremities and tendons are sliding, stretching and strengthening certain areas may help. Common stretching is mainly for the anterior, lateral and posterior calf of the hip; commonly used intensive exercises include elastic band side walking, wide squat, and medial femoral muscle activation. After professional evaluation, targeted training is more effective.
Stretch belt side walk | Courtesy of the author
Swelling and pain, most likely something went wrong
In addition to the sound itself, the most likely sign of "real illness" is accompanied by pain or swelling of the knee joint. Severe swelling can be seen at a glance, the knee joint is obviously thicker, and it even feels difficult to bend the knee and the legs are difficult to fit together.
However, when the amount of liquid is small, the appearance changes slightly, and this position is more likely to be found: sitting on the edge of the chair and straightening your legs, placing your heels together on the ground, and relaxing the muscles on the front of your thighs. If the depression around the patella flattens and the knee joint appears more "full", there may be an intra-knee effusion or extra-joint edema. If you are not sure whether it is swollen, it is recommended to go to the hospital for a more accurate examination.
The knee on the right side of the picture is normal, with a clear depression around the patella; the knee on the left side of the picture is swollen and the surface is smoother | wikimedia
The real "sick" knee ringing, that is, the source of pathological ringing, is more, the cartilage inside the joint cavity, the synovium, the bones outside the joint cavity, tendons, bursa and so on can be sounded. In terms of type, the sound may come from acute trauma, chronic degenerative changes, and systemic diseases can also affect the knee joint.
Among them, everyone often says "you are like that again, old and easy to get arthritis", usually refers to osteoarthritis, and many people have concerns about knee ringing because they are worried about this disease. Osteoarthritis will make the cartilage in the joints become rough, and the bones have abnormal protrusions, so that the friction between the bones and the bones, the bones and the surrounding tissues rub against each other during the activity, making a "squeaking" sound, and even the friction between the bones can be felt when the hands are placed on the knees.
Healthy knees | knees with severe osteoarthritis Bioventus
If there is a problem with the "buffer" meniscus in the knee joint, it may also be stuck during activity and make a "clicking" sound, such as the congenital shape of the meniscus (discoid meniscus) or the presence of damage such as tears and abnormal functions.
In addition, systemic diseases such as incomplete absorption of the inner division of the knee joint, abnormal trajectory of knee joint movement, external articular tendon sheath cysts, tendonosis, structural and functional changes after surgery, and rheumatoid arthritis may produce a sound during development.
This is when you first see a doctor to make a diagnosis, and then consult your orthopedic, sports medicine, or rehabilitation doctor about what treatment is needed, such as changing your previous exercise habits, relaxing or strengthening certain muscles, and medication, physical or surgical treatment. Don't learn the "one-stroke elimination knee noise" trick, because the sound comes from different sources and there is no treatment or rehabilitation that works for everyone.
Knee ringing is a phenomenon, it may be completely fine or it may be a serious problem, first understand the cause before deciding how to solve it.
bibliography
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Author: Dai Tian Doctor
EDIT: odette
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