Their findings are the result of a one year follow-up study of nearly 6000 Danish workers who had been surveyed previously regarding the symptom distribution and frequency of CTS.

According to a report in the Journal of American Medicine (JAMA), the researchers found “a prevalence of possible carpal tunnel syndrome between 1.4 percent and 4.8 percent based on a screening questionnaire and a clinical interview, and an incidence of new or aggravated symptoms of possible carpal tunnel syndrome of 5.5 percent.” This, concluded the researchers, “does not pose a severe occupational hazard for developing (the) symptoms” of CTS.

The goal of the study was to determine whether or not work-related keyboard and mouse use could contribute to the development of CTS. While the researchers indicated that keyboard usage probably is not linked to CTS, they did find an association between using a mouse for more than 20 hours each week and a slightly elevated risk of developing CTS. They also noted that evidence existed that linked “forceful industrial work” to the development of CTS.

These findings will come as no surprise to readers of The Ergonomics Report™. The March 2002 issue reported in detail that the link between keyboarding and CTS was tenuous at best. The article concluded with:

Common computer tasks do not appear to significantly increase the risk of carefully diagnosed CTS. Symptoms that mimic CTS and symptoms of other types of MSDs, however, are elevated among computer operators. Symptoms experienced by computer operators are thought to be multifactorial in nature, making it difficult to diagnose a single root cause, and therefore an effective course of treatment. Many of these symptoms are not indicative of permanent damage or injury, and will subside with appropriate workplace modifications or medical treatments.

The most important message is that premature, incorrect diagnosis of CTS can initiate costly, painful and unsuccessful treatments, potentially ending in permanent injury or disability.

—Dr. Peter Budnick, The Ergonomics Report, Vol. 1, No. 1, March 2002