Cramps occur when the muscles of your calf or foot suddenly become hard, tight, and painful. It is caused by muscle spasms which are involuntary contractions of one or more muscles. Though generally harmless, muscle cramps can make it temporarily impossible to use the affected muscle.
Cramps are symptoms often associated with the following conditions:
Equinus is a condition in which the upward bending motion of the ankle joint is limited.
Foot Compartment Syndrome
Compartment syndrome occurs when excessive pressure builds up inside an enclosed muscle space in the body.