Hi I'm Dr. Molly with Your Goals Physical Therapy. I was asked the same question multiple times this week. So I figured why not talk about it? I was asked, "Why is it that my knee makes this grinding noise? It almost sounds like two pieces of wood rubbing on each other when I go to stand up and sit down." The interesting thing was these people were asking me this question only as a point of curiosity, because their knee didn't actually hurt. It just sounds horrible. And so they couldn't figure out why your joint would make a noise that just sounds like two pieces of broken wood rubbing into each other, and not even hurting.
My answer started with first talking about the anatomy of your knee.
So your knee is a joint made when your Femur, your thigh bone, meets you Tibia, your shin bone. Then your kneecap, which is actually a floating bone that doesn't directly connect to anything, sits in a groove and it slides up and down in its groove.
When you bend and straighten your leg, that knee cap is supposed to just move a little bit up and down. Well, what happens with the grinding is that your kneecap is being pulled laterally to the outside of your knee and it's grinding against its little groove. The reason its being pulled to one side versus just going straight up and down the middle, is because one of your four, thigh muscles is doing more work than the other side. So it's causing an uneven pull, typically out to the outside of the knee, most people don't have the grinding because it's pulling towards the middle side of their knees, that's just not a normal pattern.
Then obviously the follow-up question is, "Well, does the noise matter? Does it make a difference that my knee sounds like two pieces of wood are grinding into each other?" I would say yes, and this is why I would say Yes. There's a reason that that sound is happening. Just like if you had one tire that was deflated and one that's fully inflated your car would be slightly wobbly. And that unevenness would cause a problem pretty quickly in your car.
Having your knee cap grinding on the outside is causing uneven wear and tear on that joint. It's not supposed to do that, not to mention if that muscle isn't doing its job, then what other things are having to adjust when you move because that muscle is just not strong enough. There's normally more than one imbalance in your knee or hip that is leading to this, particularly obnoxious noise. If I talk to people who have that grinding noise, and ask more questions about how they feel doing certain daily activities. They'll also notice that their low back or their knees get sore or tired quickly when they're doing standing activities, like dishes, going up and down stairs, sitting for long periods of time.
So it's not that the knee grinding has no other symptoms. It's just much easier to ignore the other symptoms.
So what happens when people ignore these symptoms? 10 or 15 years down the line, there's no real way to know exactly how fast it happens, there is such excruciating pain in their knees that they're asking for knee replacements at the age of 50. That is right well before 60 year old. There's so many people getting knee replacements in their 50s due to problems that started as mild annoyance in their 30s and 40s.
This is why when anyone asks me about this noise I always suggest having it looked at by a specialist. A specialist can come in and figure out exactly why it is that your knee is making this horrible grinding noise. They're gonna be able to create a very specific program for you that directly gets to the point and allows your healing process to be as short as possible. So instead of doing a general exercise program or a general stretching program, which could help your knee, it depends on which stretches you're doing and what strengthening exercises you're doing. If you come and see a specialist, they're gonna know exactly where to start, what to do and how to jump-start that progress, which will allow you to not have as much uneven wear and tear on your knee joint.
So that was my answer to the people who are asking me, and I hope that this information helps you as well.
WE HELP ACTIVE ADULTS OVERCOME THEIR ACHES AND PAINS TO GET THEM BACK TO THEIR FAVORITE ACTIVITIES WITHOUT MEDICATION, INJECTIONS OR SURGERIES.
Dr. Molly McDonald