Active epidemiological surveillance of musculoskeletal disorders in a shoe factory

(1) To evaluate an active method of surveillance of musculoskeletal disorders (MSDs). (2) To compare different criteria for deciding whether or not a work situation could be considered at high risk of MSDs in a large, modern shoe factory.

A total of 253 blue collar workers were interviewed and examined by the same physician in 1996; 191 of them were re-examined in 1997. Risk factors of MSDs were assessed for each worker by standardised job site work analysis. Prevalence and incidence rates of carpal tunnel syndrome, rotator cuff syndrome, and tension neck syndrome were calculated for each of the nine main types of work situation. Different criteria used to assess situations with high risk of MSDs were compared.

On the basis of prevalence data, three types of work situation were detected to be at high risk of MSDs: cutting, sewing, and assembly preparation. The three types of work situations identified on the basis of incidence data (sewing preparation, mechanised assembling, and finishing) were different from those identified by prevalence data. At least one recognised risk factor for MSDs was identified for all groups of work situations. The ergonomic risk could be considered as serious for the four types of work situation having the highest ergonomic scores (sewing, assembly preparation, pasting, and cutting).

The results of the health surveillance method depend largely on the definition of the criteria used to define the risk of MSDs. The criteria based on incidence data are more valid than those based on prevalence data. Health and risk factor surveillance must be combined to predict the risk of MSDs in the company. However, exposure assessment plays a greater role in determining the priorities for ergonomic intervention.