RSIs are caused by repeating the same task over and over again, such as constantly clicking your mouse or striking your keys too hard. These tasks can cause wear and tear on your body's soft tissues (tendons, nerves, etc). If care isn't taken to rest these parts, permanent damage can result.

Some of the more common RSIs are:

• Tenosynovitis – inflammation of the tendon sheath
• Tendonitis – inflammation of a tendon
• Epicondylitis – an inflamed tendon that attaches itself to the bones at the elbow
• Carpal Tunnel Syndrome – the compression of the median nerve within the carpal tunnel
• Cubital Tunnel Syndrome – compression of the ulnar nerve where it passes the elbow near the "funny bone."
• Thoracic Outlet Syndrome – affectation of the nerves and blood vessels of the neck and shoulder

• Tightness or soreness
• Throbbing or sharp pain
• Numbness / tingling / burning sensation
• Loss of strength in the hands, arms, shoulders or neck

Some of these symptoms may not reveal themselves while you're at work. Carpal Tunnel Syndrome, for instance, sometimes manifests as hand numbness or tingling while you (or them) are trying to sleep. Usually, however, your first symptom of an RSI will be localized fatigue (aches, pains, loss of strength or trembling) in the affected limb. These sensations will increase if you continue the damaging activity, but usually decrease after stopping the task. If you begin to experience any of these symptoms, contact your doctor immediately. A day or two could make a significant difference.

Factors known to contribute to RSIs:

• Monotonous or Repetitive Tasks – performing the same action with the same body part
• Posture – placing a joint toward its extreme end of movement in any direction away from its neutral or centered position
• Force – performing a task with excessive muscular exertion
• Static Exertion – holding an object or part of the body in the same position for an extended period of time
• Contact Stress – direct pressure on nerves or tendons from resting a body part on a hard or angled surface
• Exhaustion – infrequent or inflexible breaks while performing repetitive tasks

• Keep frequently-used items within arm's reach so that you needn't stretch uncomfortably to get them
• Adjust your chair so that your feet lie flat and your thighs are parallel to the floor
• Be sure to have proper support for your hands and forearms when you use your keyboard (either on a tabletop, wrist rest or the arms of your chair)
• Avoid bending your wrists for any lengthy period of time
• Adjust your typing style and keyboard position to avoid striking the keys too hard
• Get up from your desk at regular intervals and move around for a few minutes
• Knowing the risk factors and symptoms of RSIs can go a long way toward preventing them. For more information on this topic, consult your physician.