Influence of Trunk or Pelvic Rotational Movement on the Varus and Valgus Angles of the Knee: Relationship between Three-dimensional and Two-dimensional Motion Analyses

Abstract

[Purpose] The influence of trunk or pelvic rotation movement on knee varus and valgus was examined using three and two-dimensional analyses of the knee valgus angle and their relationship was investigated. [Participants and Methods] Differences between the foot-width and the postural conditions after left rotation of the trunk or pelvis by nine healthy adult female subjects were analyzed in three and two dimensions using the knee valgus angle as an index, and the correlation between the results was investigated. [Results] In three-dimensional analysis the right knee was in a varus position and in two-dimensional analysis it was in a valgus position. The right knee abducted in a 20° left pelvic rotation movement. The three and two-dimensional knee valgus angles showed a significant negative correlation only for the right knee in the posture after 10° left pelvic rotation with a foot width of 20%. [Conclusion] Left pelvic rotation affected right knee eversion, and the knee valgus angles of the three and two-dimensional analyses were different.