Musculoskeletal disorders of the hand and wrist and population attributable fraction of risk of exposure to biomechanical constraints.

OBJECTIVE: To determine the population attributable fraction (AF) related to occupational exposure to repetitive movements, in the genesis of musculoskeletal disorders (MSD) of the hand and wrist.

MATERIAL/PATIENTS AND METHODS: Cohort study of 602 people divided into two groups (exposed to repetitive movements, unexposed group), matched for age, gender, job tenure and work schedules. The study had two components: a clinical study of the MSD of hands and wrists, and a study of workstations.

RESULTS: In the exposed group, the mean age was 29.7±8.4 years and the sex-ratio was 0.08. Everybody exercised in the clothing sector, the average job tenure was 8±6.5 years. A cycle time less than 30seconds and the application of excessive force at the wrists and/or hands were found in 58.6% of exposed subjects. For the musculoskeletal disorders (MSD) of the hand and wrist, the attributable risk (AR) with exposure to repetitive movements were equal to 0.13 and the AF was 0.85. For the carpal tunnel wrists and/or hands were found in 58.6% of exposed subjects. For the musculoskeletal disorders (MSD) of the hand and wrist, the attributable risk (AR) with exposure to repetitive movements were equal to 0.13 and the AF was 0.85. For the carpal tunnel syndrome, the AR was 0.06 and AF was equal to 0.85. Regarding synovial cyst of the wrist, the AR was equal to 0.04 and AF was equal to 0.87. MSD of the hand and wrist were statistically associated with age (P<10(-3)), employment status (P=0.005), job tenure (P<10(-3)), the required manual force (P=0.001) and the required performance (P=0.002).

DISCUSSION-CONCLUSION: Rigorous ergonomic and preventive measures should be implemented to avoid the MSD of the hand and wrist installation and this by limiting the biomechanical constrains including repetitiveness.