What makes a knee pop?

[motorcycleman]

My left knee pops every time I straighten it from being bent about 90 degrees or more. It dosen't hurt and I can't relate it to any injury. Should I see a doctor? Is it safe to ride my bicycle?

[Fast Forward]

My guess would be it is the sound/sensation of the patella (knee cap) as it travels over the femur. It might not be gliding perfectly over the femur and causes a pop. When you squat down from a standing position do your knees make a crackling/crunching sound?

[motorcycleman]

yes, it does

[noodle]

This happens to me sometimes.

A few years ago when I was going through a growth spurt. If my left knee was bent back as i went to straighten it, it would some thies just lock. And it killed to try and change the angle of my knee. Then after just moving it a slight bit, something would line up and i could straighten it with no pain. One time I just couldn't get it to unlock and my dad took me to the hospital. Some doctor for some reason just started pulling on it to straighten it out and made the loudest thump, and it straightened out. Sometimes it happens as I straighten my leg but I dont realise quick enough and it just forces it unlocked.

[sirceo26]

This happens to me sometimes.

A few years ago when I was going through a growth spurt. If my left knee was bent back as i went to straighten it, it would some thies just lock. And it killed to try and change the angle of my knee. Then after just moving it a slight bit, something would line up and i could straighten it with no pain. One time I just couldn't get it to unlock and my dad took me to the hospital. Some doctor for some reason just started pulling on it to straighten it out and made the loudest thump, and it straightened out. Sometimes it happens as I straighten my leg but I dont realise quick enough and it just forces it unlocked.

o man thats gotta suck

[scottmotox]

ouch!!

[2 stokes for life]

Hey I have the same thing with my right knee. Has never been the same after poping out the backside and having my friend slam it back in. I have also hit a quad rear rack in 3rg gear pinned with all the force going into the knee alone.

Now it pops every morrning and makes loud pops when squated past 90 deg and now there is a bunch of build up of something, but the doc said it would go away with time but it has been like it for 1 year or so.

So I would be interested as to what it might be.

[XCfunrunner]

Where does it hurt when you extend it out?

[Fast Forward]

yes, it does

Sure sounds like the patella tracking issue I mentioned above.

[cleancutdesigns]

hmm.. I had a similar problem. everytime I crouched down like a baseball catcher or sat indian style when I would get up it would kinda pop and it got worse and worse until when it popped i couldnt walk on it for a week at a time.

Finally got it checked out and after artho surgery I had two big tears in my meniscus. They cut one out and stiched the other and it hasnt done it since.

[pyrofreak]

Noodle, the same thing happens to me sometimes. From a softball injury. I was told it was a muscle issue and my kneecap moving too much to one side. Did countless leg raises/wieghts/etc. Finally just gave up on it and try not to "tuck" my legs underneath me when I sit. I dont "sit on my heels" type squat, and don't sit indian style either. It helps.

[fmv60691]

popping can be nothing (if it doesn't hurt) or could be a sign of something going wrong. Get an MRI and a doc to see it. My popping led me to a bilateral condromalacia patellar. Make sure your patella is well aligned and also that your quadriceps is well equilibrated in its both sides