Different neuromuscular parameters are associated with knee abduction and hip adduction angles during functional tasks.

Knee abduction and hip adduction during functional tasks may indicate increased joint injury risk and discriminate between pathological and healthy people. Muscles' neuromuscular variables such as amplitude (EMG _AMP ) and onset (EMG _ONSET ) have been used to explain kinematics. The study aimed to evaluate the correlation between two EMG variables of seven trunk and lower limb muscles and 3D kinematics during two tasks. Eighteen physically-active women participated in the study. The following variables were obtained during single-leg squat and anterior step-down: (i) EMG _AMP and EMG _ONSET of fibularis longus (FL), tibialis anterior (TA), vastus medialis (VM), biceps femoris (BF), gluteus medius (GMED), ipsilateral (OB_IL) and contralateral (OB_CL) external obliques and (ii) knee abduction and hip adduction angular displacement (initial angle - angle at 60° of knee flexion). Spearman's correlation coefficient was calculated between kinematic and EMG variables. Greater knee abduction was correlated with delayed TA _ONSET , GMED _ONSET and OB_IL _ONSET during step-down. Greater hip adduction was correlated with lower VM _AMP , BF _AMP and delayed VM _ONSET during step-down. Although task-specific, these results suggest that EMG _ONSET may influence knee abduction, while both EMG _ONSET and EMG _AMP may affect hip adduction. The identification of muscle activation patterns in relation to kinematics may help the development of injury prevention and rehabilitation programs.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)