Cumulative trauma disorders: their recognition and ergonomics measures to avoid them.

Cumulative Trauma Disorders, CTD, are the summary results of many microtrauma. Though known since the early 1800s, they have become a matter of urgent ergonomics concern in the 1980s. They are usually caused by repeated and/or forceful exertions, often in the hand-arm-shoulder region. They predominantly occur to soft tissues, such as tendons and ligaments, and to nerves and blood vessels. They are commonly associated with certain occupational and leisure activities. Many CTD can be avoided by a set of fairly simple and straightforward ergonomics procedures.