OCCUPATIONAL AND PERSONAL RISK-FACTORS FOR CARPAL-TUNNEL SYNDROME IN INDUSTRIAL-WORKERS

Objectives The purpose of the study was to evaluate both nonoccupation al and occupational factors associated with carpal tunnel syndrome (CT S) in industrial workers. Methods Sixty-five workers with CTS were com pared with 65 referents matched for gender, age, and plant. The medica l history and household activities' of the workers and the ergonomic a nd organizational characteristics of the job were analyzed. Results Ex ertion of force over 1 kg was associated with CTS [odds ratio (OR) 9.0 ]. Two risk factors were related to motion repetitiveness: length of t he shortest elementary operation of less than or equal to 10 s (OR 8.8 ) and lack of change in tasks or lack of breaks for at least 15% of th e daily worktime (OR 6.0). No posture of the upper limb was associated with CTS. Workstation design involving the manual supply of the worke rs (OR 5.0) and the lack of job rotation (OR 6.3) were associated with CTS. The only personal factor associated with CTS was a parity of at least 3 (OR 3.2). There was a continuous increase in the odds ratio ag ainst the number of risk factors accumulated by the workers; the odds ratio thus ranged from 5.6 when 3 of the 6 risk factors were present t o greater than or equal to 90 when 4, 5, or 6 risk factors were accumu lated. Conclusions The results were in agreement with a model for CTS which included 1 personal and 5 occupational risk factors. The number of risk factors cumulated by the workers seems to be a major determina nt of CTS.