José Antonio Diego Mas
The study makes a significant contribution to our understanding of the effectiveness of ergonomic interventions for workers with musculoskeletal disorders of the arm, neck or shoulder. The review’s methodology is rigorous and systematically assesses the quality and certainty of the available evidence. Its findings do not show clear short-term benefits from the ergonomic interventions studied in alleviating existing musculoskeletal discomfort, which provides valuable information for guiding action strategies. Furthermore, the review also finds that ergonomic interventions are likely to produce a small reduction in pain in the long term, with evidence of moderate certainty.
However, it is important to interpret the scope of the research and its conclusions correctly. It should be borne in mind that the fundamental role of occupational ergonomics is to intervene before work-related health problems arise, by identifying, assessing and reducing risk factors, rather than attempting to correct their consequences once they have manifested. In other words, the primary objective of occupational ergonomics is preventative, rather than therapeutic or reactive. This review, by contrast, analyses the effectiveness of specific ergonomic interventions as a treatment for workers who already suffer from these conditions. These are two distinct objectives, and findings relating to one cannot be directly extrapolated to the other. Therefore, this study does not provide evidence that calls into question the preventive role of occupational ergonomics; rather, it highlights the limitations of the available evidence regarding its use as a treatment. It would be a mistake to interpret these results as an argument for reducing preventive ergonomic measures in the workplace.
Whilst the review is valuable, it has some limitations that must be taken into account. The authors acknowledge that all the included trials present a high overall risk of bias, as well as heterogeneity in the interventions analysed and a predominance of studies involving office workers. This limits the possibility of generalising the results to other work environments. Furthermore, the term ‘ergonomic intervention’ encompasses a wide range of very different measures, from simple postural recommendations or training to modifications to equipment; the review does not allow for a systematic assessment of the extent to which these measures succeeded in reducing exposure to biomechanical risk factors. Therefore, interpreting its conclusions as a general demonstration of the ineffectiveness of ergonomic interventions would go beyond what the data allow us to conclude.