Pointing Devices

Today’s computer software has resulted in prolonged or repetitive use of pointing devices such as mice and trackballs. Upper extremity and back discomfort can result from improper use of these devices for extended periods of time.

Here are some possible solutions to reduce or eliminate pain related to pointing device use.

• Limit the use of the pointing device as much as possible. The best remedy for a pointing device injury is rest. Take breaks every 15-20 minutes and change position frequently when working.
• Make sure that your pointing device is positioned correctly. Your pointer should be at the same level or slightly higher than your keyboard and within easy reach. You should be able to work with your arms close by your sides, your elbow at approximately 100 to 110 degree angle, and your wrists in a straight or neutral position.
• Be cautious of using the "ergonomic" keyboards that are spread out wide if you have narrow shoulders. Wide keyboards result in the pointer being positioned further out to the side.
• A mouse bridge can be used to position your mouse or trackball closer to you if you do not need to use your keypad.
• Some users have found that switching the pointing device from the right side to the left side of the keyboard allows them to use it with their arm in a more relaxed position. This allows them to place the device closer to their center front by avoiding positioning to the outside of the keypad on the right. Give yourself time to get used to switching hands.
• If you use a mouse and are experiencing shoulder pain, try switching to a trackball. A trackball reduces the need to complete upper arm movements by utilizing the smaller forearm muscles. Start gradually and build up your tolerance.
• Avoid overuse of your thumb when using a trackball. Use caution before purchasing a trackball that uses the thumb to roll the ball.
• If your work requires repeated button clicking, try using a mouse or trackball that requires low force levels to activate the button.
• Use a pointer with a scroll button option if you scroll frequently (especially if you are a web surfer).
• Select a pointing device that is the right size for your hand. A painful ring or little finger may result from a pointing device that is too large or too small for you. Evaluate your hand size in relation to the device. The device should fit comfortably with the palm of your hand in a neutral position.
• Avoid prolonged holding of the pointing device. If you are not using the pointing device, let it go.
• Do not hold your pointing device too tightly. Use a light grasp and touch.
• Avoid holding your finger above the activation buttons when using the pointing device. Relax your fingers when not using to operate the trackball or buttons.
• Customize your pointing device software to meet your particular needs. The size, speed, and response of your pointer can be controlled for efficient operation. Make sure you slow down the response speed if you tend to overshoot your target. This can double your workload.
• Use a pen stylus with caution. If you need to use one, select it with care. Make sure it is comfortable to grasp. If possible try alternating with a puck stylus to use different muscles.
• If you do graphic work, use a tablet. Make sure the tablet is large enough for you to use comfortably.
• Reduce intensive mouse use whenever possible. Incorporate keyboard shortcuts or alternatives into your work techniques. The following are some commonly used shortcuts:

For additional information, contact the Ergonomics Specialists at EH & S at 45590. Or visit our website: www.ergonomics.ucla.edu