Whiplash is a relatively common injury that occurs to a person's neck following a sudden acceleration-deceleration force that causes unrestrained, rapid forward and backward movement of the head and neck, most commonly from motor vehicle accidents. The term "whiplash" was first used in 1928. The term "railway spine" was used to describe a similar condition that was common in persons involved in train accidents prior to 1928. The term whiplash injury describes damage to both the bone structures and soft tissues, while "whiplash associated disorders" describes a more severe and chronic condition. Fortunately, whiplash is typically not a life threatening injury, but it can lead to a prolonged period of partial disability. There are significant economic expenses related to whiplash that can reach 30 billion dollars a year in the United States, including:medical care,disability,sick leave,lost productivity, andlitigation.