Repetitive strain injuries are caused by a combination of stretching and twisting the arm to keep your hand flat on the mouse. To avoid repetitive strain injuries and discomfort, it’s important that your computer mouse is a perfect fit for your hand and provides optimal support and comfort. You need to have a relaxed grip that doesn’t bend your fingers too much, otherwise your hand and wrist can become strained, causing injuries. An ergonomic computer mouse such as Unimouse or Contour Mouse promotes correct hand placement and means you avoid the unnatural hand position that often occurs when using traditional mice.