Computer-related injuries
RSI
What are RSIs?
The Repetitive Stain Injuries (RSI), also called Cumulative Trauma Disorders (CTD) or Muscular Skeletal Disorders (MSD), are injuries damaging muscles, tendons and nerves, due to repetitive tasks like type writing. They affect the upper part of the body: hand, wrist, arm, elbow, shoulder, neck, back.
Who is at risk?
Anybody whose work involves small, repetitive hand movements like computer users, musicians, cashiers, hair dressers, sewing machine operators, farmers (cow milking), workers in the electronic industry.
How to prevent RSI?
Take short breaks several times a day and stretch your hands, wrists, neck and back. Adopt the right position in front of your computer. Try ergonomic keyboards and find the one which suits you best.
CTS
The Carpal Tunnel Syndrome is a common RSI among computing scientists. The symptoms include pricking in the hands, sharp pains, strength loss.

The carpal tunnel is the space between the ligament and the wrist bones. By this tunnel the median nerve goes from the fingers up to the brain and allows the brain to control the fingers. The tendons of the finger muscles surround the nerve and if they become swollen, the median nerve is compressed and can be damaged.

The tendons slide within a tube. This tube produces a liquid lubricating the tendons. When the hand moves repetitively or excessively, the lubrication can become inadequate. Therefore the tendons can rub against the tube and become swollen.

Back pain
Back pains are related to bad postures when working in front of a computer.

What are the causes?
The major causes are an improper keyboard and table height and a chair without any back or lumbar support.
How to prevent?
To prevent back pains, the spine S-curve has to be maintained: first by raising the chair and table, then by adjusting the chair and changing positions and postures regularly. Ergonomic chairs allow you to adjust the arm rests, to control the height and to support the lumbar vertebrae. A foot rest can help too.
Eye strain
An eye strain is a discomfort in the eye. It can occur after spending a long time at a computer monitor. The various symptoms are eye irritation (like dry, watery or red eyes), difficulty focusing, double vision, blurred vision. Backaches, headaches or muscle pains can occur too. To prevent eye strain, the screen should be a little further away than the usual reading distance, its top should be slightly below eye level and the lighting of the room should be set so that glares and reflections are minimised. A filter for the monitor can also help.
Vitamin D deficiency
Vitamin D is a fat soluble vitamin, which means that it is stored
in the human body when there is too much of it. It allows the body to
absorb calcium.
Food is only a minor source of vitamin D and it is mainly manufactured
in the skin when it is exposed to sunlight. Young people who get
little exposure to sunlight, spending summer afternoons at a computer
game for example, can be vitamin D deficient. This results in weak
bones and nerves not working properly.
Conclusion
Computing scientists should be careful in the way that they work! Some new graduates can suffer from CST just one year after their graduation! Only a few simple precautions need be taken to prevent these painful and debilitating conditions.
- table, chair, screen and keyboard height
- chair posture
- room light
- regular breaks
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