What is CTS?

CTS stands for "carpal tunnel syndrome," which receives its name from the eight carpal bones located in the narrow space in the wrist. When the ligaments or tendons become enlarged, usually due to inflammation, carpal tunnel syndrome can develop. CTS is only one of many forms of RSI, but it is the one that computer users are most likely to develop.

For years, sufferers of CTS were told that their pain and symptoms were a figment of their imagination. Scientific research has not only confirmed the existence of this RSI, it has also demonstrated that CTS has the potential to cause disability. That said, very few CTS sufferers require invasive surgery -- the remainder recover with proper treatment and prevention measures.

While the number of cases of CTS has risen, it is often incorrectly used as a catch-all term for anyone experiencing pain in the wrists and forearms. Some individuals who present with CTS-like symptoms actually have acute to chronic tendonitis or extreme muscle tightness (7).

While most experts on RSI and CTD agree that poor ergonomics at work usually play a major factor in developing these conditions, Pete Egoscue believes otherwise:

"People with carpal tunnel syndrome or other computer-related pain symptoms have 'blisters' in their wrists. There is friction and stress. These blisters are not caused by using a PC's keyboard or mouse. They are caused by the adjustments that are made to skeletal misalignment" (8).

There is no clear answer as to why some people who perform the same amount and type of action develop CTS while others do not. It may be a combination of factors, including vitamin deficiencies, wrist shape, posture, overall health, physical condition, work habits and response to stress.

Main causes of CTS:

Inflammation of the flexor tendons due to overuse. Any occupation or hobby that requires the constant movement of the hand from extension to flexion (i.e. grocery checkers or circulation clerks) makes this tendon susceptible to injury.
Misalignment of the carpal bones.
Any occupation that directly compresses the carpal tunnel itself. The main culprit in this case would be the use of a computer mouse. Resting the hand on the mouse pad and extending the hand and fingers to click the button puts direct pressure on the carpal tunnel.
Any occupation involving vibration, such as the operation of a jackhammer or chainsaw.
Cold environmental temperatures as it causes decreased blood flow to the tissues. Individuals who work in cold environments are much more susceptible to CTS.
Previous wrist fractures that have changed the carpal bone structure (9).

For more on occupational health and safety, visit the Centers for Disease Control's National Institute for Occupational Safety and Health.

Symptoms

CTS has a very specific pain pattern. The most common symptoms of CTS are:

Tingling or numbness in the thumb, index and middle fingers along with pain in the wrist and possibly the forearm.
Pain traveling up towards the elbow.
Clumsiness and weakness in the hands.
Difficulty holding objects such as cups and paper.
Sensations of burning or coldness.
Pain may also interfere with sleep.

Sufferers often ask why symptoms seem worse at night; Tammy Crouch provides this answer:

"One explanation for this common pattern is that blood flows through your system much slower at night, which can enlarge the blood vessels of the carpal tunnel. The increased amount of blood puts pressure on the nerve. This may account for the increased numbness, tingling and pain some people experience at night" (10).

There are three stages of carpal tunnel syndrome: stage I involves mild symptoms with negative test results; stage II includes moderate symptoms with positive results from orthopedic and/or neurological testing; and stage III involves moderate to severe symptoms with significant abnormalities on the electromyographic studies.

For stage I, the usually treatment involves a rest period, a massage or a session with a chiropractor or physical therapist. Implementing ergonomic solutions at work are usually very effective at this stage.

For stage II, longer rest periods are usually prescribed, plus extended periods of wearing a splint or brace and more frequent therapy. Depending on the extent of the nerve damage, a full or partial recovery can be achieved in conjunction with lifestyle changes, or, the condition can worsen.

Stage III carpal tunnel syndrome is defined as moderate to severe symptoms that persist for more than one year or if electromyographic tests show significant abnormalities. At this point, there is significant damage to the median nerve and conservative treatment is unlikely to relieve symptoms. At this point, medical intervention is necessary to prevent further nerve damage (11).

It is important to note that there is no perfect cure for every individual suffering from CTS. Developing CTS is not inevitable ‚ by taking preventative steps and self-monitoring, it can be avoided.

For more information on carpal tunnel syndrome, including a full-colour diagram of the carpal tunnel, see the Mayo Clinic's article on CTS.