Abstract
[Purpose] This study aimed to clarify the kinematic characteristics of thorax displacement associated with trunk rotation. [Subjects and Methods] The subjects were 13 healthy young adults. The subjects performed left and right trunk rotation to the endpoint 4 times. The rotation angle of the thorax relative to the pelvis and the displacement of the thorax center relative to the pelvis center were measured using a 3D motion analysis system. [Results] During trunk rotation, the thorax mostly moved in the anterior and lateral directions relative to the pelvis. Specifically, the lateral movements were in the opposite direction to the rotation. [Conclusion] The results of this study suggest that the thorax moves forward and to the opposite side of trunk rotation in a complementary manner.
