Knee pain and popping is a common problem and can be caused by a number of factors. Another term commonly used for popping in the knee is Crepitus, which essentially means a noisy joint, whether it be popping, clicking, cracking or snapping.
The final type of erosion is attrition. Attrition is a way of eroding the riverâs load, not the bed and banks. Attrition is where pieces of rock in the riverâs load knock together, breaking chunks of rock off of one another and gradually rounding and shrinking the load.
2. 1  Attrition is the mechanical wearing down of the biting and chewing surfaces of teeth. 2  The tooth to tooth contact during chewing grinds down the surfaces. 3  The back teeth become flatter, and the front teeth become shorter.. 1  Attrition is the mechanical wearing down of the biting and chewing surfaces of teeth. 2  The tooth to tooth contact during chewing grinds down the surfaces. 3  The back teeth become flatter, and the front teeth become shorter.