Trackballs & Tendonitisby Carolyn Csanyi
Computer users often suffer from skeletomuscular complaints due to repetitive movements associated with using mouse pointing devices. The trackball uses different muscles to operate and is considered less stressful to use, but some problems have been associated with it as well.
The trackball houses a ball that can be rotated to control cursor movement. Since the trackball can remain stationary, unlike the mouse, it takes up a smaller footprint. It is effective for rapid and precise cursor movement.
Trackballs can be used with lower shoulder extension and less neck and shoulder activity, but they use more wrist extension than mouse operation. Doug Fine, in an InfoWorld article, notes that trackballs require less lateral arm motion and are worth consideration for someone beginning to experience symptoms.
At an Israeli Intel plant, workers using trackballs complained of wrist pain and discomfort. An ergonomic study revealed that extending the workstation trackball's angle from 9 degrees to 24 degrees allowed the wrist to be held in a more neutral position, alleviating symptoms.
San Francisco Study
Workers at a San Francisco call center were evaluated for wrist tendonitis, elbow tendonitis and muscle strain in the upper back and neck based on using trackballs and forearm supports. Dr. David Rempel, head researcher, found that using forearm supports was effective in lowering the incidence of neck, shoulder, hand, wrist and forearm pain among the workers.
- photo_camera Trackball image by bnstrong from Fotolia.com