Glossary of Common RSI Terms

Here are definitions of some of the more common terms associated with Repetitive Strain Injury.

Bursitis

A bursa is a small fluid-filled sac located between movable parts of the body, especially at the joints. Its function is to decrease the friction between two surfaces. Bursitis is an inflammation of a bursa. The swelling increases friction, and movement becomes pained and irritating. Repetitive movement or prolonged excessive pressure can cause bursitis.

Carpal Tunnel Syndrome

The Carpal Tunnel is a narrow passage between the bones at the bottom of your wrist through which nerves, arteries, and tendons pass. If the lining of the carpal tunnel becomes irritated due to excessive finger and up-down wrist movements, it swells causing pressure on the median nerve. This can cause numbness, tingling, loss of grip power, and a tendency to drop objects. Fortunately only a minority of RSI cases involve carpal tunnel syndrome.

CTS

See Carpal Tunnel Syndrome.

CTD

Cumulative Trauma Disorder. Another name for RSI.

De Quervain's Disease

This is a special name given to tenosynovitis at the base of the thumb. This can be caused by too tight a grip on a mouse, or by repetitively hitting the space bar with the thumb with excessive force.

Dorsiflexion

Bending your wrist upwards, rather like a policeman stopping traffic. This will happen if you type with your wrist leaning on the desk or if your keyboard is at the wrong height.
See RSI Prevention Tips for an illustration.

Epicondylitis

An inflammation of the elbow joint. If it's on the outside of the joint, it's more commonly known as Tennis Elbow; if it's on the inside of the joint, it's known as Golfer's Elbow.

Ganglion Cysts

A Ganglion Cyst is a small bump or mass that forms underneath the skin, often at the wrist or finger joints. They are formed when the tissue surrounding a joint swells up with lubricating fluid. They can swell up when the joint is irritated. Often they are harmless, and may disappear on their own if the source of irritation is removed. However, they may sometimes be associated with pain or tenderness and restriction of movement. Overuse of fingers and wrists may give rise to ganglion cysts.

Hiirikyynärpää

Finnish term for computer-related RSI. Literally Mouse Elbow.

Mausarm

German term for computer-related RSI. Literally Mouse Arm.

Muskoskeletal Disorder (MSD)

The medical grouping of injuries which involve muscles rather than bones. Examples include carpal tunnel syndrome, tendinitis, muscle strains and back pain. Repetitive Strain Injuries fall in this category.

Muisarm

Dutch term for computer-related RSI. Literally Mouse Arm.

Musarm

Swedish term for computer-related RSI. Literally Mouse Arm.

Museskade

Danish term for computer-related RSI. Literally Mouse Injury.

Neutral Wrist Position

Position in which the wrist is neither bent to one side, nor bent up or down.
See RSI Prevention Tips for an illustration.

OOS

Occupational Overuse Syndrome. Another name for RSI. The primary term for RSI in New Zealand.

Phalen's Test

Test frequently used in the diagnosis of Carpal Tunnel Syndrome. The patient holds both hands together in a praying position, but with the backs of the hands rather than the palms of the hands touching each other. This position contorts the carpal tunnel, and mildly pinching the median nerve. If, after a minute, the patient starts to feel tingling in the thumb, index, or middle finger, it suggests the possibility of carpal tunnel syndrome.

Radial Deviation

Bending your wrist towards your thumb. (The Radius is the bone in your arm on the same side as your thumb).
See RSI Prevention Tips for an illustration.

Radial Tunnel Syndrome

This problem is caused by the radial nerve becoming compressed or entrapped at the outside of the elbow. Symptoms can occur at the elbow where the nerve is trapped, near the base of the thumb, or anywhere in between.

RMD

Repetitive Motion Disorder. An alternative term and slightly more general term for RSI.

RMI

Repetitive Motion Injury. An alternative term and slightly more general term for RSI.

RSI

Repetitive Strain Injury. A musculoskeletal injury resulting from prolonged repetitive, forceful, or awkward movements. This includes conditions such as tendinitis, bursitis, ganglion cyst, tenosynovitis, trigger finger, and Carpal Tunnel Syndrome (CTS). Frequently (but not exclusively) refers to computer-related RSI from keyboard or mouse use, but can also refer to other injuries (such as back pain) caused by repetitive work tasks.

Repetitive Strain Injury

See RSI.

Repetitive Stress Injury

Common mistyping of Repetitive Strain Injury. In physics, stress is force per unit area, and strain is the proportion of its length by which an object deforms under the effect of stress.

Tendinitis

Tendinitis (also known as tendonitis) is inflammation of the tendons. Tendinitis occurs frequently in the shoulders, elbows, and forearms. If an aching pain is not associated with any specific muscle, it is often caused by tendinitis. Tendinitis can also impair the grasping of objects.

Tendon

Connective tissues that attach muscle to bone. They have very little stretch or rebound. If stressed due to overuse or maintaining a stretch for an excessive time they may get small tears. Friction from overuse may also result in inflammation. This condition is known as Tendinitis.

Tendonitis

Common misspelling of Tendinitis.

Tenosynovitis

Where tendons curve round bones and change directions, they pass through tendon sheaths. Irritation caused by the rubbing of the tendon and the sheath is known as Tenosynovitis.

Thoracic Outlet Syndrome

Muscles need a supply of oxygen rich blood. WHen arteries and nerves are compressed, they no longer receive it. Possible symptoms include pain in the entire arm, numbness, coldness, and weakness in the fingers, hand, and forearm. Symptoms can increase after carrying heavy loads, or by working in a position with the arms elevated (changing lightbulbs, writing on a whiteboard).

TMS

Troubles Musculo-Squelettiques. French term for RSI.

Trigger Finger

An irritation of the digital sheath that surrounds the flexor tendons of the finger. The sheath becomes thickened or swollen, preventing the tendon form gliding smoothly. Sometimes the tendon may catch then suddenly release, leading to an effect rather like the sudden movement when a trigger is released.

Ulnar Deviation

Bending your wrist towards your little finger (the Ulnar is a bone on the same side of the arm as your little finger).
See RSI Prevention Tips for an illustration.

WRULD

Work-Related Upper Limb Disorder. Another name for RSI.

WMSD

Work-related Musculoskeletal Disorders. A term used by the Canadian Centre for Occupational Health and Safety for RSI.

WRMSD

Alternative acronym for WMSD for Work-related Musculoskeletal Disorders. An alternative term for RSI.