The mouse is a common piece of computer equipment which helps peopleuse computers more quickly and easily. Since the introduction ofWindows technology in the 1990s, which made mouse-intensive softwarepopular, the mouse has become standard office equipment.
Using a mouse as the only input device (as with a computer game) isnot hazardous as long as the computer workstation is set up properlyand frequent breaks are observed. However, because most people using amouse in a workplace setting must use the computer keyboard at the sametime, using a mouse regularly works the same small muscles over andover again, and can lead to discomfort, pain, and even WorkplaceMusculoskeletal Disorders (WMSDs).
What makes using a computer mouse hazardous?
There are two reasons why using a mouse regularly can be hazardous.
First, using a mouse requires a person to make small, exactmovements with their hand, fingers, and thumb. By positioning,travelling, scrolling, and clicking the mouse again and again, the samesmall muscles can become tired and overworked. This can cause:
* Pain (ache, soreness) on the top of the hand (Figure 1)
* Pain (ache, soreness) around the wrist (Figure 1)
* Pain (ache, soreness) along the forearm and elbow (Figure 1)
* Formulation of painful nodules, and in the later stages, ganglion cysts, around the joints and along the tendons
* Numbness and tingling in the thumb and index finger that may develop into Carpal Tunnel Syndrome (CTS)
The second reason using a computer mouse can be hazardous is thatthe placement of the mouse can make it awkward to reach. Many computerworkstations have limited space; since the keyboard is already directlyin front of the person using the computer, most times the mouse isplaced around the upper right hand corner of the keyboard and towardthe back of the desk (Figure 2).
When the mouse is in this position (Figure 2), it is out of 'easyreach': it is beyond the safe distance range for comfortable handmovements. In order to use the mouse, the person has to reach their armoutwards and forwards (Figure 3) and hold it there unsupported for aslong as they are using the mouse.
Moving like this, and holding your arm like this, again and againthroughout the workday can cause soreness and fatique by putting anextra load on the muscles in the upper back (Trapezius muscle) andshoulder (Deltoid muscle). Repeated use of the mouse, therefore, cancause aches and pains in the shoulder and neck area. Lower back pain,while not directly caused by the mouse, can also be a problem if thecomputer user has poor posture and leans forward when they sit.
What can be done to reduce the risk of injury from using a computer mouse?
Designing a computer workstation which lets a person use a keyboardand a mouse (or other input devices like trackballs or graphicstablets) at the same time can be very difficult.
The complete elimination of aches, pains, and WMSD may not bepossible, but choosing the right mouse, positioning it properly, andbeing aware of how you are holding your body and using your muscles canall help.