I'm 31 years old and my knees creak when I bend them. If I squat really low, they'll also make a popping sound. I've had this for years, but it seems to be getting louder. I haven't had any other problems with my knees, and it hasn't stopped me from running. Is it a sign of wear and tear, and should I be concerned that it will turn into something serious later? - J.N.
Creaky knees are a common and benign occurrence - as long as your knees are pain-free. However, if your knees hurt, become swollen, stiffen, lock or give out on you, that's a totally different story.
Pain is a marker for joint inflammation, and knee effusions (water on the knee) are signs that the knee is creating more fluid to increase lubrication and cushioning to an injured knee. Locking or suddenly giving way can be signs that your cartilage is irregular, torn, or even that there are bits of it floating free within the knee joint.
Some people will have front-of-the-knee pain that signals a kneecap not tracking straight in it's groove, wearing the underside of the patella down.
People can expect more of these chronic knee problems as they gain weight, lose muscle strength in the glutes, hamstrings and quads (the muscles that support the knee joint and absorb shock), and as they age.