The effect of computer use on carpal tunnel syndrome

Carpal tunnel syndrome (CTS) is the most prevalent of all repetitive strain injuries (RSIs). The Bureau of Labor Statistics [1] determined that there was an average of 26,972 reported cases of CTS annually, between the years 1992 and 2006, in private industry. To understand the effects computer use has on CTS, it is necessary to identify the movements involved in performing everyday tasks such as typing and mouse usage. Motion analysis techniques were employed to determine these movements while performing a computer task. This involved markers being placed on the knuckles, wrists and forearms of the participants. The con figuration of the markers allowed for the flexion, extension, radial deviation and ulnar deviation of the wrist to be calculated. The results were categorized in one plane of motion with 20∑ extension being the most prominent wrist posture. The most common position in two planes was also calculated with an Ext20° Ulnar15° (20° extension and 15° ulnar deviation) accounting for over 3.5% (3.6%) of the total wrist posture during the task. This study determined that the most common wrist positions found in two planes provide an accurate representation of wrist position for computer use. From the results in this study a more exact indication of the wrist positions used in computer tasks have been identified. The results suggest that the wrist position in two planes should be considered when calculating the impact of computer use on CTS as it may have a bearing on the carpal tunnel pressure (CTP) created.