Hi, thanks for writing to HCM.
A grating or crunching noise arising during movements of a joint indicate degenerative changes in the articular surfaces ( wear and tear of the cartilage
Normally the joint surfaces are smooth ,so they wont produce any noise when they move over the other. But in a degenerated joint, the surfaces will be rough and hence will produce noise while they move.
In the initial stages, there may not be any symptoms.
Consult an orthopedic surgeon and follow his advice accordingly.
Hope this information is helpful. Good day