Michigan State University

Ergonomic Definitions

Carpal Tunnel: Carpal tunnel syndrome is caused by pressure on a nerve (the median nerve) in the wrist. The symptoms include tingling, numbness, weakness, or pain felt in the fingers, thumb, hand, and sometimes into the forearm. Both work and recreational activities can cause carpal tunnel syndrome if done over a long period of time. (Source: WebMD)

Ergonomics (or human factors): Ergonomics is the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance. (Source: IEA Ergonomics Human Centered Design)

Repetitive Motion Disorders (Cumulative Trauma Disorders, Repetitive Stress Injuries, Overuse Syndrome): Repetitive motion disorders (RMDs) are a family of muscular conditions that result from repeated motions performed in the course of normal work or daily activities. RMDs include carpal tunnel syndrome, bursitis, tendonitis, epicondylitis, ganglion cyst, tenosynovitis, and trigger finger. RMDs are caused by too many uninterrupted repetitions of an activity or motion, unnatural or awkward motions such as twisting the arm or wrist, overexertion, incorrect posture, or muscle fatigue. RMDs occur most commonly in the hands, wrists, elbows, and shoulders, but can also happen in the neck, back, hips, knees, feet, legs, and ankles. The disorders are characterized by pain, tingling, numbness, visible swelling or redness of the affected area, and the loss of flexibility and strength. For some individuals, there may be no visible sign of injury, although they may find it hard to perform easy tasks Over time, RMDs can cause temporary or permanent damage to the soft tissues in the body -- such as the muscles, nerves, tendons, and ligaments - and compression of nerves or tissue. (Source: National Institute of Neurological Disorders and Stroke)

Repetitive Tasks: Activities involving sustained or repetitive musculoskeletal exertion with no opportunity for rest or recovery. Examples of repetitive tasks are: pinching/grasping books, lifting, bending, answering a telephone, keyboarding and mousing.