Definition of True cramp

True cramp: A cramp that involves part or all of a single muscle or group of muscles that usually act together such as, for example, the muscles that flex adjacent fingers. True cramps are caused by hyperexcitability of the nerves that stimulate the muscles. They are the most common type of muscle cramp and are different from the other three main types of cramps: tetany, contractures, and dystonic cramps.