지각 불편도에 근거한 복합 몸통 동작 분류 체계 - 굴곡/신전 및 회전

Abstract

Objective: This study aims to investigate effects of complex trunk motions including flexion/extension and rotation, and external load on perceived discomfort, and to develop a new load classification scheme for complex trunk motion and external load based on the perceived discomfort.<BR><BR>Background: For preventing low back pain, postural stress for low back or trunk motions should be quantified. The posture classification schemes such as RULA, REBA frequently used in industrial sites classify trunk motions into 4 or 6 categories according to motions of flexion and extension, and simply add 1 to their corresponding postural stress scores if the trunk is twisted or laterally bended. This is very simple to assess complex trunk motions, but results in inaccurate trunk motion stress.<BR><BR>Method: An experiment for measuring perceived discomfort according to complex trunk motions and external load was conducted, in which trunk motions of flexion/extension and rotation, and external load were used as independent variables. Discomfort according to complex trunk motion and external load was measured by using the Borg CR10. Sixteen healthy male college students without histories of musculoskeletal disorders participated in the experiment, whose demographic data were as follows: Age - 23.7 ± 0.60 years; Stature - 174.1 ± 4.67cm; Body weight - 67.4 ± 6.82kg.<BR><BR>Results: ANOVA showed that single factors of flexion/extension, rotation, and external load affected significantly on the discomfort at α = 0.01. The effect of external load was much larger, while the effects of flexion/extension and rotation were smaller and similar. Based on the experimental results, a new classification scheme quantifying effects of external load as well as complex trunk motions was developed and validated. <BR><BR>Conclusion: This study investigated effects of complex trunk motions including flexion/extension and rotation, and external load on perceived discomfort, and developed a new classification scheme of complex trunk motion and external load.<BR><BR>Application: The results of this study will help to more precisely assess postural load according to complex trunk motions and external load.