Abstract
There are many reports of the joint angles measurement of extremity during standing motion. The joint angles are calculated from two segments connected two points of markers on the body surface (Method 1). On the other hand, there is a method that calculates joint angles from the two segments connected two coordinate points of the center of joint from model analysis (Method 2). The purpose of this study was to compare of the angles calculated by the two methods in sit-to-stand. The subjects were five healthy males. Sit-to-stand movement was captured and analyzed using three dimensional analysis system (Oxford Metrics VICON370). Then hip, knee and ankle joint angles were calculated by the two Methods. Results indicated there was significant difference between hip and ankle joint angles calculated the two methods. Because spinal movement is included in the Method 1 of the hip angle calculated and Method 2 is not. Ankle angles was differ because vector directions of each segment, siliqua-fifth caput ossis metatarsaliss in Method 1 and center of ankle joint-second caput ossis metatarsaliss in Method 2, were different of two Methods. The other joint angles measurement compared in this study were found no significant difference. These results will give cues to estimate angles corresponding to every center of joints targeted from angles measured from the body surface points.
