For all those who spend many hours at the computer:
The position of the hands when handling the mouse or keyboard is critical. It´s important to know that the wrist is a joint with many small bones, and that placing them under tension for a long time by bad positioning can create a dysfunction in their structure, leading to pain caused by tiny areas of swelling, and this can be associated with tendinitis.
Here is a simple drawing of good and bad positioning of the wrist with the mouse, so as to avoid possible anomalies produced by incorrect posture.