Back pain is one of the most prevalent work-related conditions for physical therapists. Patient transfer is the most common physical therapist work activity related to back injuries, which is more frequently performed by physical therapists than other medical professionals. Therefore, this study aims to identify the risks by investigating the correlations among physical therapists' work analysis evaluation and workload awareness, and muscle activity according to the patient's transfer period and compare those differences between periods of patient transfer. The number of subjects in this study was 17, and the period of the simulated patient's transfer was divided into three motions(lifting, holding and rotating, lowering). Moreover, work analysis evaluation, workload awareness, and muscle activity were measured each period. For work analysis evaluation, rapid entire body assessment(REBA) was used, and muscle activity was measured for the erector spinae, gluteus maximus, and medial hamstrings using an electromyogram analyzer. In addition, workload awareness was collected after each subject was written after the experiment was finished. Correlation analysis was used to find out the correlation of variables in each period, and repeated measures ANOVA was used to find out the difference in patient transfer variables(work analysis evaluation, workload awareness, muscle activity). For statistics, SPSS 26.0(IBM SPSS Inc. USA) was used and the significance level(α) was set at 0.05.
There was a very high correlation between work analysis evaluation and workload awareness and right erector spinae muscle activity, in the lifting period of the patient transfer(p<0.01). In the holding and rotating period, there was a high correlation between work analysis evaluation and right erector spinae muscle activity, workload awareness and erector spinae muscle activity, work analysis evaluation and workload awareness(p<0.01). In addition, there was a very high correlation between work analysis evaluation and right erector spinae muscle activity in the lowering period(p<0.01).
In work analysis evaluation according to patient transfer, the lifting period had the highest risk, and the workload awareness had the highest risk for the lowering period(p<0.05). The muscle activity of the erector spinae was the highest during the lifting period(p<0.05), the right gluteus maximus showed no significant difference(p>0.05), and the left gluteus maximus showed the highest activity during the lifting period(p<0.05). In addition, the medial hamstring showed the highest muscle activity in the lifting period(p<0.05).
In this study, most of the measured variables of patient transfer showed that the lifting period was the most dangerous, but workload awareness was said to be more dangerous for the lowering period because psychological factors acted greatly for the reason that the simulated patients were actually used in this study. These results will contribute to revealing in which period a physical therapist should pay more attention during patient transfer, and consequently, to future studies on a real patient transfer. In addition, they could be used as basic data for research on patient transfer or work-related risks of physical therapists, or for developing a musculoskeletal symptoms prevention program.