Computer Mousing Tips

Tips for Using a Computer Mouse

The following tips, found on Cornell University’s Ergonomic site, should help you avoid a mouse-related musculoskeletal injury. The same posture principles apply to other input devices (e.g. trackball, touchpad, pen, digitizing puck etc.). Postural variation is a key factor for good ergonomics. Try to regularly vary your posture when you work with a mouse, and in this way you will help to minimize the risk of ergonomic problems. remember, the best ergonomic mice are designed to allow you to vary your posture while working with the mouse.

1. Mouse grip - Don't throttle your mouse (it's already dead)! Hold the mouse gently to move it over a mousing surface.
2. Mouse from the elbow - Don't skate or flick the mouse with your wrist. Make controlled mouse movements using your elbow as the pivot point and keep your wrist straight and neutral.
3. Optimal mouse position- Sit back in your chair, relax your arms then lift your mousing hand up, pivoting at the elbow, until your hand is just above elbow level. Your mouse should be positioned somewhere around this point. Don't use a mouse by stretching to the desk or out to the side of a keyboard. With a flat mouse platform, position this 1-2" above the keyboard and over the numeric keypad if you are right handed - you can easily move it out of the way if you need to access these keys. With a downward sloping mouse platform, position this close to the side of the keyboard so that you can use the mouse in a neutral wrist position.
4. Protect your wrist - If you look at the anatomy of the wrist, it is curved away from any contact surface (you can easily see this by resting your hand/arm on a flat surface - you'll see light under the wrist and can probably even pass a thin pen under this). The forearm is shaped liked this for the wrist to remain free of surface pressure contact.
5. Avoid restricting circulation - For may people there are exposed blood vessels near the skin at the wrist, which is where the pulse is often taken. Any pressure in this region will disrupt circulation into the hand and this will increase the risks of injury.
6. Avoid restricting arm movement - With a softly padded wrist rest, especially one that is rounded, or a soft chair arm rest, the forearm becomes "locked" into position and this encourages people to make mouse movements by flicking the wrist, which also increases intra-carpal pressure.
7. Keep the mouse free moving - The base of the palm of the hand is the part of the body designed to support the hand when resting on a surface. For keyboard use, a broad palm support is best. However, mouse use is different from keyboard use. With a keyboard, the best posture is for users to float their hands over the keyboard when typing and then to rest on the palm support in micro-breaks between typing bursts. With mousing this doesn't happen. A mouse is used by moving its position over a surface and resting usually occurs when mouse movements stop but with the mouse still being held in the hand. Mouse movements should be made using the elbow as the pivot point, not the wrist. Anything that impairs free movement of the forearm/hand and mouse will increase injury risks.
8. Mouse shape - Choose a mouse design that fits your hand but is as flat as possible to reduce wrist extension. Don't use a curved mouse. Use a symmetrically shaped mouse. Consider a larger mouse such as the Whale mouse or the Perfit mouse, that encourage arm rather than wrist movements or that encourage postural variety and one or two-handed use. Pen-based mice designs also allow a more comfortable grip.
9. Load sharing - If you want to load share between your right and left hands, you’ll need to choose a mouse platform that can easily be configured to the left or/and right and a symmetrical shaped mouse that can be used by either hand.
Other input devices - Whether you choose a different mouse design, a trackball, a joystick, a pen, a touchpad, a multi-touch pad or some other input device, make sure that you position it comfortably and that your wrist is in a neutral position when using the device.

Summary recommendations for mouse position:
If you are using your mouse on a surface then:
• Best arrangement for a mouse is a platform over the number keypad and just above the keyboard.
• Good arrangement is a pad on an angled platform to the side of the keyboard.
• Poor arrangement is a flat surface to the side of the keyboard
• Worst arrangement is on the desk out to the side of the keyboard.