Development of a System to Support Self-learning of Body Mechanics for Nurses to Prevent Back Pain : Development and Validation of a Self-checking System of Movement-implementing Body Mechanics

Background With the aging of society, the problem of lower back pain in medical and nursing care environments is becoming increasingly serious. In response, we have identified that the implementation of body mechanics during caregiving procedures represents an effective way of preventing back pain in nurses. However, body mechanics cannot be fully effective unless nurses recognize and acquire the skills of movement to implement body mechanics and learn how to apply those skills when actually caring for patients. It is important for nurses to evaluate objectively how they move when caring and to learn and acquire the knowledge and skills of body mechanics according to individual requirements. Purpose The purpose of the study was to develop a self-learnable "system for self-checking movement-implementing body mechanics", so that any individual who applies the system can objectively evaluate their movements when giving care and subsequently prevent back pain by implementing body mechanics. Nursing course students were used for experimental application and validation of the system. Based on the results, the usefulness and learning effects of the system were discussed. Methods 1. System development: The "system for self-checking movement-implementing body me chanics" was developed so that users of the system could self-check by looking at video images of their posture, joint angles and EMG, and the lumbar load (moment of the joint as determined by angle of anteversion of the body) displayed on the computer screen during movements. Computer images were generated by inputting data on joint angle taken from the unilateral ankle, knee, hip joint and lower back and EMG data taken from bilateral erector spinae muscles and the unilateral biceps femoris muscle. In addition, the system included a storage and playback functions for measurement data to facilitate user learning from watching the images. 2. System validation: To validate the system and learning effects, the following experiment and investigation were performed in January 2006.1) Two nursing course students performed "bed making (triangle corner setting)" and data obtained from the system was subjected to the system validation experiment. This experiment was designed to be performed under 4 different sets of conditions to compare lumbar load with or without the application of body mechanics and with beds of different height. 2) A total of 22 nursing course students participated in a model class lesson for body mechanics application using images replayed based on data obtained from the experiment, and the display function of the system and learning effect were evaluated. Result 1. System validation: Images of posture, joint angle, EMG waves and lumbar load during caregiving movements of the subject were clearly displayed in real time or playback on the screen and validity of the system was confirmed. The results of evaluation indicated, however, that some evaluation items scored as low as 2. 90 points, with comments such as "I do not understand what the displayed numbers mean". 2. Learning effects of the system: The learning effects of the system were evaluated using a 5 -point scale. Mean score was 4. 04 for "Understanding the importance of application of body mechanics", and 4. 09 for "Intention to evaluate and learn self movement using the system". Scores for these items by the 2 students who actually experienced application of the system were even higher, indicating that the learning effects with self-checking using the system are likely to be high. Conclusion Using the system, self-movement was subjectively evaluated from the perspective of body mechanics. The usefulness of the system was validated and learning effects for application of body mechanics were identified. The importance of improving the system display and learning function are suggested as future issues.