The current rating for the determination of risk from biomechanical overload of the upper limbs during pruning operations with traditional shears, refers to quantifications methodologies which are based on estimates of subjective operators interviewed during operations. The OCRA method (Colombini and Occhipinti, 1996, 2005) is the procedure recommended by the international standards EN 1005-5 and ISO 11228-3 for the risk assessment overload due to repetitive movements of upper limbs. This research was based on laboratory pruning tests monitored through a surface electromyograph. The pruning operations were performed by a sample of seven healthy operators who performed the cutting, always in the same position, on shoots collected by vineyards during the winter pruning. The branches were collected from four different cultivars of vineyards and were divided into groups of two diameters (<5 mm and 8-12mm). The electromyograph was monitored by medical personnel and acquisitions were saved for subsequent processing. The muscle activity was detected by EMG via surface electrodes placed on the skin of forearm muscle. In this case, the isometric situation is not too complex, and the number of muscles involved is small, especially as the biceps and brachioradialis muscles are involved in a synergistic way. The processing of data collected during the operations conducted in the laboratory, allowed to observe the ability of the clinical test to read and interpret the effort made by the muscles of the arm of the pruner. The correlation between the peak values of muscular effort and the diameters of the branches was analyzed in order to have a dimensional confirmation. It was also developed an analysis of variance in order to statistically show significant influences of the factors considered during the test, on the results of muscular effort pointed out from medical records. These results have highlighted the involvement of affected muscle groups, providing new insights into the risk assessment of pruning.
|Titolo:||A clinical test to research objective values of effort during manual pruning|
|Data di pubblicazione:||2012|
|Appare nelle tipologie:||4.1 Contributo in Atti di convegno|