# A Review on Ergonomics in Agriculture. Part II: Mechanized Operations
## 5 Discussion  
Operation of agricultural machines contributes to the development of MSDs, which is an increasing international concern, since they constitute the most common non-fatal health problem among rural workforce [7; 11]. Ergonomics is the research field that aims at fitting the task to workers by improving the workers-workplace environment and helping them to avoid awkward postures and vibrations. To this end, interventions are pursued by designing and evaluating ergonomic equipment as well as informing workers about the body postures that should not be acquired. The present systematic bibliographic survey identified 32 relevant journal papers regarding ergonomics in mechanized operations in agriculture. An additional criterion was imposed, namely all articles had to be published in the last decade, in order to capture the up-to-date progress in this field and determine the principal risk factors for MSDs. The preliminary data visualization analysis, which was conducted, gave a sense of the geographical distribution of the most productive research organizations. It was ascertained that the present studied issue interests both developing and developed countries worldwide, with the major contribution being originated from Italy, Sweden and New Zealand. Ergonomics in agricultural machinery was proved to be a versatile and interdisciplinary topic concerning fields such as agrotechnology, occupational ergonomics, manufacturing, computational modeling and medicine. Furthermore, using the tool developed by [PERSON] et al. [42], the methodological quality of the studies was found to be either high or acceptable, thus, corresponding to low and moderate risk of bias, respectively. The most investigated agricultural machines were, at decreasing order of frequency, tractor, quad bike, grass trimmer and handheld olive beater, as well as power tiller, rice plowing machine and agricultural aircraft. The three last machineries were presented with equal percentage. Each machinery was described in a different subsection in order to examine the investigated ergonomics in depth. Triaxial accelerometer was the main instrument that was utilized to measure the vibration levels during operating the machines under various conditions. In addition, a lot of the selected studies implemented special questionnaires, which investigate the consequences of operating agricultural machines. In particular, special forms of the WBV health surveillance questionnaire [80], Nordic questionnaire [81] and other MSDs-related questionnaires were implemented. Useful results can be derived from these questionnaires. However, they cannot offer medical diagnosis and a careful examination by experts is required. A risk assessment analysis was also performed with the intention of identifying and evaluating potential factors that can negatively impact agricultural workers. Risk assessment is definitely an inherent portion of a wider management strategy for the purpose of introducing control measuresand developing ergonomic interventions to attenuate any risk-related concerns. It was observed that WBV and HATV are the main risk factors among the operators of agricultural machines having driving seats and handgrips, respectively. A special section was introduced prior to the results section, namely Section 2, regarding the involved biomechanics and health effects of vibration for the sake of better comprehension of the present analysis. On one hand, the agricultural machineries with driving seats, such as tractors and all-terrain vehicles, were seen to be related to painful disorders of the low back and neck. Important factors affecting the WBV are the ground unevenness, driving speed and implements. On the other hand, handheld agricultural machines, such as grass trimmer and power tiller, are responsible for disorders at the upper extremities. Commonly reported disorders are the white finger syndrome, numbness and clumsiness to perform complex operations.