Creating A Safer Workspace:

Repetitive Strain Injuries, or RSI's as a result of computer use are a growing problem for all computer users. At Moriyama & Teshima we have been conducting ongoing resarch into the causes of RSI, prevention of injury and possible cures. This page has some general information. We also have some Quick Tips, and how we reconfigured the workstations in our own office.

Causes of RSI:

RSI is the result of a combination of factors. The main causes include prolonged repetitive, forceful and awkward hand movements, poor posture, workers who ar not 'in shape', poorly fitting furniture and badly designed keyboards. Combine this with a heavy workload and the pressure of deadlines and injury will eventually occur. You may think, "it has not bothered me until now, I will be alright" but this attitude leaves you vulnerable to injury. Fine movements repeated thousands of times a day strain muscles and tendons in the forearms, wrists and fingers that actually causes microscopic tears. As the cycle is repeated over time, chronic long-term problems can result.

Resting your hand on the desk and bending you wrist backwards is very bad. This is called dorsiflexion (see the diagram to the left). This problem is the same with a keyboard or a mouse. The tilt of most keyboards is actually opposite to the way it should be. Your wrists should curve down as shown in the second diagram. Use a similar technique when using the mouse or a stylus.

Input Devices:

For us, the mouse has caused the most problems. The workload is concentrated on one hand and often one finger instead of being distributed. Combine this with a work surface which is too high and it will contribute to shoulder and neck problems. Gripping the mouse too tightly and using excessive force to click is harmful. Trackballs can be worse because they rely on fine wrist and finger motion even more. Do not rest your wrist and forearm on the table while moving the mouse. This makes the wrist and hand do all the work that must be shared with the arm and shoulder. Move your entire arm and not just your wrist or fingers. A wrist rest should be used as a guide and your whole arm should float above it. The same rules apply when using a stylus. Use a light touch.

Posture:

Take a look at these two diagrams. If you sit like the person on the left you are asking for trouble. The person on the right is doing much better. Even the best furniture is useless if not adjusted and used properly. Good work habits must come first. Since the problem is not that well understood yet by designers and manufacturers the definitive workstation solution is not yet available.

Breaks and Stretching Exercises:

Take a five minute break for every half hour of constant computer use. Once an hour, get up from your chair, move around, do something else and stretch. Do stretching exercises every day. It brings oxygen rich blood to the muscles, releases tension and reduces pain. Keep moving. Don't stay static at your desk for hours. Listen to your body. Trust your instincts. Read the warning signs. If you do not, it can lead to pain and perhaps in time some permanent disability.

Source:
REPETITIVE STRAIN INJURY - A Computer Users Guide
Emil Pascarelli, MD and Deborah Quilter