Q. I am a 40-year-old active recreational athlete. I work out at the gym at least three days a week and play soccer on the weekends. About three months ago, I felt a pop in my left knee while playing.

Q: My knee makes a popping sound sometimes — should I be concerned? A: Knee noises can be unsettling, but they're not always a cause for concern.

The popping or cracking noise many people notice while squatting, climbing stairs or stretching after sitting for long periods is medically referred to as crepitus. According to Dilip Chand Raja S., ...