A "crunching” in your knee when you crouch or squat may signal that you have the start of a degenerative condition called chondromalacia patella, a form of arthritis.
This is a condition of abnormal wear-and-tear, and Is commonly caused by aberrant tracking of the patella, or kneecap. The kneecap is embedded in the tendon of the quadraceps (quads) muscles, and every time you bend your knee back or forth, which activates these muscles, the kneecap slides in a grove in the bone underneath.
Misalignment of the patella causes it to rub too far sideways in that groove. What causes this misalignment? Commonly, it is uneven action in the quads.
My treatment is two-fold---correction of the patellar misalignment with the Activator instrument, and teaching the patient how to do daily exercises to correct the action of their quads.