1727, from Japanese samurai warrior, knight, originally the military retainer of the daimio, variant of saburai, nominal form of sabura(h)u to be in attendance, to serve..
The bubbles make a noise when they burst. This is called cavitation. Another cause for painless popping in the knee is when the ligaments and tendons catch as they go over a bony lump and pop when they snap back into place. Or the clicking and popping may be caused by catching on soft tissue or scar tissue within the knee.
Chondromalacia Patella. Chondromalacia patella is when there is softening and damage to the cartilage on the back of the patella (kneecap). This leads to front knee pain, swelling and clicking/grinding noises when moving the knee.he most common symptoms of Chondromalacia Patella are: 1) Front Knee Pain: tends to be achy rather than sharp. 2) Pain On Stairs: tends to worse going downstairs rather than upstairs. 3) Pain After Prolonged Rest: when you first get up after sitting down for a while.