Work-related upper extremity musculoskeletal disorders among computer programmers in a selected software company in the eThekweni Municipality

Abstract

Background: Upper extremity musculoskeletal disorders (UEMSDs) are a significant and common occupational health concern, impacting work attendance and performance. A high prevalence rate of UEMSDs has been reported among computer users yet limited research has been conducted on computer programmers’ specifically. Certain studies have linked these higher prevalence rates to typical daily computing tasks including prolonged sitting, incorrect ergonomics, awkward/abnormal postures and repetitive movements, but limited research has been conducted on this population specifically.

Objectives: To determine the point and lifetime prevalence of UEMSDs of the sample population of computer programmers in a selected software company in the eThekwini Municipality; to determine the injury profile of the population and compare to international studies; to identify selected risk factors of the population (demographic, ergonomic and physical risk factors); and to determine any associations between prevalence and selected risk factors of injury in the population.

Methods: This was a quantitative, descriptive, questionnaire-based survey conducted to assess selected associated risks factors for UEMSDs in computer programmers in a selected software company. Participants who met the inclusion criteria (N = 155) were invited to complete self-administered questionnaires. The study population consisted of computer programmers in a selected eThekweni software company, over the age of 18 years, who worked full-time for 8 hours or more per day, that were symptomatic or asymptomatic concerning UEMSDs.

The scores for each sub-group were expressed as percentages and summarised using mean, standard deviation and range, with 95% confidence intervals. Bivariate associations from categorical variables were conducted using a Pearson’s chi-square test or Fischer’s exact test as appropriate. Cross tabulations were conducted using contingency tables to determine whether there was an association between variables. Graphical representation of scores by groups were conducted using various types of tables and graphs such as bar graphs, tables, and pie charts. Factors were entered individually into the model to evaluate their Pearson’s chi-square values and partial Eta scores. A p value of < 0.05 was considered as statistically significant for the Pearson’s chi-squared test; a partial Eta score greater than 0.14 was considered as highly significant.

Results: Of the 155 completed questionnaires, the lifetime prevalence of work-related UEMSDs in the sample population was 41.3% and the point prevalence of 21.9% in the upper limb. The lifetime prevalence of the three most common anatomical areas affected were the right shoulder at 25.8%, the right wrist at 23.9% and the right hand at 17.4%. The point prevalence of the three most common anatomical areas affected were the right shoulder at 9%, right wrist at 7.7% and right hand and left shoulder both at 4.5%. There was a large effect size with increasing age and severity in lifetime prevalence (ƞp2 = 0.200) and a medium effect size in point prevalence (ƞp2 = 0.084). There was a large effect size in increasing age and duration of injury in both lifetime (ƞp2 = 0.244) and point prevalence (ƞp2 = 0.282).

Fourteen point seven percent of the participants took sick leave and 85.3% of the affected sample population have some degree of productivity loss in point prevalence. Incorrect workstation setup and type of injury was a high-risk factor in work-related injury in both point and lifetime prevalence in this study. Ethnicity and gender were not risk factors in this study. Increasing age, a history of sports injury, increased work experience (p = 0.021), increased working hours per week (p = 0.012), increased hours on the computer per week (p = 0.001) and overtime (p = 0.018) were shown to have a statistically significant association with UEMSDs. Participants who worked > 40 hours on the computer per week were prone to injury 16.769 (O.R.) times more often than participants who worked 20 to 30 hours on the computer per week (p = 0.037) and 3.563 (O.R.) times more often than a programmer who worked 31 to 34 hours per week (p = 0.013). Cofounding risk factors to injury were sick leave (p = 0.000) and productivity loss/work interference (p = 0.000).

Conclusion: This is the first South African study, to our knowledge, that highlights point and lifetime prevalence rates for work-related UEMSDs among computer programmers as well as significant DASH findings. This draws attention to the need for implementation of intervention programmes to prevent and/or reduce the development of work-related UEMSDs.