Effects of hip and trunk kinematics on peak frontal plane knee moments during sidestep cutting: A cross-sectional study

Abstract

Most ACL injuries occur during non-contact sporting situations during single leg landing or cutting maneuvers. The ACL can be loaded by external frontal plane knee moments. Studies have observed the associations in kinematics of the hips and trunk with knee valgus moments during a long timeframe of the stance phase of a landing or cutting maneuver. ACL injuries, however, occur during the first 100 ms of the stance phase and therefore it is important to analyze the associations of kinematics of the hips and trunk and knee moments during this time, which could be different. A cross-sectional study was conducted on 105 participants at the age of 14-17 years old. With anatomical and tracking markers secured on the participants, they performed sidestep cutting maneuvers on a force plate while a camera system from Qualysis recorded data from the markers and force plates. Peak frontal plane knee moments, hip and trunk kinematics of 2236 sidestep cuts during the first 100 ms of the stance phase were analyzed in visual 3D. Linear and multiple regressions were conducted to examine the associations of hip and trunk kinematics on peak frontal plane knee moments. Regression results showed significant associations of hip abduction, hip internal rotation, hip internal rotation excursions and trunk lean to the stance leg with peak knee valgus moments during the 100 ms of the stance phase. Hip internal rotation, hip external rotation excursions and trunk lean to the stance leg were associated with peak knee varus moments. The influence of hip and trunk kinematics on peak frontal plane knee moments was small and may therefore not be important regarding ACL injuries.