In grappling, an armlock is a single or ouble joint lock that hyperextends, hyperflexes or hyperrotates the elbow joint and/or shoulder joint. An armlock that hyperflexes or hyperrotates the shoulder joint is referred to as a shoulder lock, and an armlock that hyperextends the elbow joint is called an armbar. Depending on the joint flexibility and integrity of a person, armlocks that hyperrotate the shoulder joint can also hyperrotate the elbow joint, and vice versa.