When I squat, my left knee makes all kinds of noise. And not once, but really a series in a row. It does not really hurt, but I’m worried. And it’s just not a nice sound. Do you have any idea what this can be?
Mark Chen, Physiotherapist
Sounds in joints are very common and exist in various forms, for example, there’s “snaps”,”pops” and “cracks”. Sometimes they are a one-time thing but they can also be constant, as you describe in your question. I can immediately reassure you; 90% of all knees crack, and as long as there is no pain, there is no clinical value. This rule of thumb applies to all sounds joints make.
The knee is a bit special when it comes to sound-making and that is mainly due to the kneecap. Visualise the kneecap as a kind of boat, which lies in the bony groove of the upper leg. There’s cartilage between the kneecap and the femur for smooth movement.
If both surfaces are smooth, there would probably never be any sounds. But that’s not how it works for most people. There are countless factors that determine how our knee is loaded and how the cartilage is stressed as a result. Think of sports, work (for example road workers) and footwear. These factors allow the structure to adjust. A “rippled” structure of your cartilage is very normal, but it does provide a bit more friction when there is a lot of pressure on the kneecap. For example, in squatting.
If you still worry after this explanation, there are ways to change the direction of your kneecap. As long as you do not experience pain, however, you do not need to take any action as far as I am concerned. Ask around in your own environment who else has noisy knees and you will be surprised. And in Dutch, we have a saying that would translate to something like this:
“creaky cars go the longest” , let’s hope that applies to your knees as well!