Musculoskeletal problems and ergonomic risk assessment in rubber tappers: A community-based study in southern Thailand

This study aimed to evaluate the prevalence of musculoskeletal disorders and ergonomic risk levels, and identify ergonomic factors related to low back pain in rubber tappers. A cross-sectional survey was conducted in Chumporn Province, Southern Thailand. Subjects with a history of major trauma or certain pre-existing back disorders were excluded. A questionnaire-based interview, pain self-report form, direct observation of the workers, and a video-based analysis of working postures using the Rapid Upper Limb Assessment (RULA) method were used. Over half (52.9%) of the participants had low back pain during the previous 3 months, while the prevalence of pain in the legs, upper arms, neck, wrists, and lower arms were 14.8%, 8.9%, 3.0%, 2.3%, and 2.1%, respectively. The average final RULA grand score of 5.25 corresponded to an action level of 3, which indicated the need for prompt medical investigation and work habit changes. From logistic regression analysis, the tapping levels and tapping postures including high frequencies of twisting, bending, and extension of trunk were significantly associated with low back pain. Other independent risk factors included a high frequency of weight lifting, high perceived fatigue from work, and lower levels of social support, education and income. Rubber tapping is regarded as an occupational risk for musculoskeletal disorders (MSDs). An abnormal ergonomic factor in rubber tapping increases the risk of low back pain among rubber tappers. Preventive measures should be developed to minimize this problem in the future.Relevance to industryThe results of this study suggested the need for the development and implementation of a program using ergonomic concepts to reduce low back pain for rubber tappers.

► Low back pain was the most common MSDs in our participants (52.9%), followed by leg pain (14.8%).
► An average RULA score of 5.25 indicating that the average worker needed action level 3.
► No participants had an acceptable RULA score of 1 or 2.
► Ergonomic factors related to low back pain were tapping levels, the frequency of twisting, bending and extension of trunk.
► Perceived fatigue from work, social support, educational level, and income were also statistically significant.