This Web site, hosted and supported by
Carnegie Mellon University, is all about putting concerns for your health
first and not taking chances with bad typing habits. Your hands might
not hurt today, but they may tomorrow. And then it might be too late to
do something about it.
"RSI" actually stands for Repetitive Strain Injury.
Sounds easy enough, but unfortunately, it's not that easy to define. There
are several different types of RSI and there are different symptoms for
each one. We will do our best, using this Web site and other resources,
to let you know how to avoid injury.
Types of Injuries
The following types of injuries are often associated with Repetitive
Adverse Mechanical Tension (AMT):
Muscle spasms in your shoulders cause the nerves that run down your arm
to contrast and compress. This injury is also known as "neural tension,"
and can be misdiagnosed as another RSI disorder. AMT can be treated and
reversed with physiotherapy.
Carpal Tunnel Syndrome (CTS):
The nerves that run through your wrist into your fingers get trapped
by the inflamed muscles around them. Symptoms include feeling "pins and
needles," tingling, numbness and even loss of sensation.
Tendons can become inflamed through repeated tensing. Eventually,
the fibers of the tendon start separating, and can even break, leaving
behind debris that induces more friction, more swelling, and more pain.
"Sub-acute" tendonitis is more common, and is a dull ache over the wrist
and forearm that gets worse with repetitive activity.
The tendon sheath thickens and becomes inflamed when repetitive activity
exceeds the sheath’s ability to lubricate the tendon. As a result, the
area around the sheath becomes tender and painful.
A special case of tenosynovitis that occurs in the abductor and extensor
tendons of the thumb where they share a common sheath. This condition
often results from combined forceful gripping and hand twisting.
Thoracic Outlet Syndrome (TOS):
The nerves and vessels between the neck and shoulders compress from
long periods of hunching or raising your shoulders. Symptoms include pain
in wrist/hand and lack of pulse in the affected arm. The last two fingers
of the affected hand may be numb, tingle or turn blue due to a lack of
The symptoms or RSI include:
- Stiffness or pain in your neck, shoulders or back
- Tiredness, numbness, tingling or pain in your arms, wrists, hands
- Clumsiness or loss of strength and coordination in your hands
- Pain that wakes you up at night
- Feeling a need to massage your hands, wrists and arms
These symptoms do not simply "happen." There are many factors
that add up and lead to RSI. Those factors are covered in the section
of this Web site titled "Am I at Risk."
Ergonomic Terms and Definitions
Creating a good ergonomic work environment can help you avoid RSI. The
following are some terms and definitions related to ergonomics.
The science that seeks to adapt work or working conditions to suit
you, the worker.
Repetitive Strain Injury:
Excessive wear and tear on tendons, muscles, and sensitive nerve tissue
caused by continuous use over an extended period of time.
Keeping your body in its natural alignment.
Movement that decreases or increases the angle between two bones.
Bending your hand at the wrist in either the direction of or away
from the thumb.
An irritation of muscles in your neck, commonly occurring after repeated
or sustained work.