Creatively coined crepitus, one still might picture those 3-little guys sitting on the edge of the cereal bowl just waiting for the milk to smother the ingredients down at the bottom creating a symphony of, what we know to be snap-crackle-and popping. However, that symphony may not be music to your ears when your knees do it, as it can mean a malfunction of the mechanics between the muscles around your knee and the position your kneecap is sitting in.
Could it be hip related? Sure. Could it be foot related? Absolutely. Could it be hip/thigh/knee/foot related? You know it!
And that cracking or grinding around or under the knee cap when you are walking up or down stairs, or while squatting to pick something up off the floor, can occur at any age!