Thanks for posting your query,
Feeling a crunching or hearing a popping sound when bending the knee, such as when bending down into a squat, are signs that cartilage
has worn away and is not protecting the bones from friction.It is a feature of knee osteoarthritis
I would suggest getting this evaluated by an orthopedician for an accurate diagnosis and appropriate management. You may get the X-ray of the area affected under his/her guidance.
I hope this information has been both informative and helpful
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Dr Saurabh Gupta.