Carpal tunnel syndrome and its relation to occupation: a systematic literature review

Objectives To assess occupational risk factors for carpal tunnel syndrome (CTS), we conducted a systematic literature review. Methods We identified relevant primary research from two major reviews in the 1990s and supplemented this material by a systematic search of the MEDLINE and EMBASE biomedical databases from the start of the electronic record to 1 January 2005. Reports were obtained and their bibliographies checked for other relevant publications. From each paper, we abstracted a standardized set of information on study populations, exposure contrasts and estimates of effect. Results Altogether, we summarized 38 primary reports, with analyses based either on a comparison of job titles (22) or of physical activities in the job (13) or both (3). We found reasonable evidence that regular and prolonged use of hand-held vibratory tools increases the risk of CTS > 2-fold and found substantial evidence for similar or even higher risks from prolonged and highly repetitious flexion and extension of the wrist, especially when allied with a forceful grip. The balance of evidence on keyboard and computer work did not indicate an important association with CTS. Discussion Although the papers that we considered had limitations, a substantial and coherent body of evidence supports preventive policies aimed at avoiding highly repetitive wrist-hand work. There is a case for extending social security compensation for CTS in the United Kingdom to cover work of this kind.