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    Knee makes crunching/cracking sound when extended
    sh4ne posted:
    My knee makes a cracking/crunching sound when extending, especially if I balance on one leg. This started happening (I think) after I was in a drum corps in the summer of '09, a rigorous activity combining marching and music. I do not remember having any serious fall or injury to my leg, but I wouldn't be surprised if I did fall or hyper-extend my leg at least slightly at some point (not enough to cause concern or any extended pain). The activity consists of lots of twisting and direction changes.

    The knee has not bothered me significantly since I was in the activity, but a cracking/crunching sound has always stuck with me. It is NOT a popping sound, but rather a sort of crunch coming from inside my knee, behind my kneecap. I can run and walk fine, but I did notice after a run the other day that my right knee (the one with the cracking sound) is a bit more sore than the other and simply feels a little different than the other (though the sound it makes may be just making me uncomfortable).

    Through my research I have narrowed it down to possibly an minor ACL injury, but I'm not sure.

    Here is a video of me bending and extending my knee a few times, with a very audible crunching sound.

    I am wondering if this is anything to be worried about, or whether I should see a Sports Medicine doctor or someone who can help with rehabilitation. It especially concerns me because if I want to do that summer drum and bugle corps activity again, I wouldn't want to cause further damage to my knee(s).

    Thanks for any advice and input.
    Melissa R Cere, PT, DPT responded:
    Hi there. Hearing noises from your joints can be a bit un-nerving. Quite often, though, those types of joint noises are due to faulty mechanics in the joint (such as the joint between the back of your knee cap and your knee). Over time, it can lead to early wear and tear to the cartilage lining the joint so it usually good to address it early to prevent pain in the future. You could certainly see a MD to evaluate your knee, but it sounds like a physical therapist could also provide you some guidance in an appropriate rehab program to correct the underlying strength and flexibility imbalance that often can be a contributing factor. You can find a PT near you at
    Take care,
    sh4ne responded:
    Thanks for the reply, Melissa.

    I visited a PT yesterday and was told not to worry too much or limit my physical activity unless I begin experiencing pain. She described the sound as crepitus and the diagnosis as chondromalacia patella which is a fairly common diagnosis for people that do a lot of running, skiing, cycling, etc. or are over the age of 40. I was given some pretty basic exercises to do to strengthen my leg muscles.
    Melissa R Cere, PT, DPT replied to sh4ne's response:
    Glad to hear you were able to get checked out by a PT. Hopefully the exercise program will help keep you on track so that you can prevent developing knee pain in the future!! Let me know how things go!
    Silenstep94 responded:
    Hey shane, was wondering what workouts you was givin, I sorta have the same problem, and it isn't possible for me to get this problem checked out, thanksss

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