Differences of the Range of Hip External/Internal Rotation Influence the Way Healthy Subject Stand Up from the Floor and Trunk Muscle Activity

Abstract

[Purpose] The purpose of this study was to clarify the influence of the range of hip external/internal rotation on the way we stand up from the floor using hip rotation range of motion and trunk muscle activity. [Subjects] In this study, 38 subjects (19 male, 19 female, average age 21.2±0.7) participated after we obtained their informed consent. [Methods] We measured hip external/internal rotation range of motion and classified them into 2 groups. Then, we classified movement patterns of standing up from the floor into three types based on hip rotation range differences. [Results] The hip large external range of motion group stood up with hip external rotation. Also, the multifidus muscle activity when standing up from the floor with hip external rotation was decreased significantly. [Conclusion] We conclude that the external/internal rotation of the hip joint influences movement patterns and trunk muscle activity in standing up from the floor.