座位での側方移動における僧帽筋の機能に関する一考察

抄録

Lateral shift in sitting is indispensable in daily life, and it has a big influence on the activities of daily living (ADL) in standing-up and walking. The purpose of this study was to clarify the function of each fiber of the trapezius-muscle during lateral shift in sitting by normal subjects using surface electromyography. The integrated electromyogram (IEMG) of the trapezius muscle in the non-shift side, tended to increase. Specifically, in the lower part fiber trapezius muscle, IEMG at 20 cm distance was significantly greater than others. On the other hand, IEMG of the trapezius muscle in the shift side tended to increase with the lateral distance of movement. In the middle fiber of trapezius muscle, IEMG at 20 cm distance was significantly greater than others. It was thought that the activity of the fiber of the lower part of the trapezius muscle in the non-shift side participated in braking the upper part of the trunk inclination which accompanies the increase of the distance. It was thought that the activity of the fiber of the middle part of the trapezius muscle in shift side participated in preservation of the controlled scapula. To stabilize the upper part of trunk to improve sitting, it is necessary to aim at the function of the fiber of the lower part of the trapezius muscle in the non-shift side.