Sigward Susan M, Cesar Guilherme M, Havens Kathryn L
Human Performance Laboratory, Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, California.
Clin J Sport Med. 2015 Nov;25(6):529-34. doi: 10.1097/JSM.0000000000000155.
To compare frontal plane knee moments, and kinematics and kinetics associated with knee valgus moments between cutting to 45 and 110 degrees, and to determine the predictive value of kinematics and ground reaction forces (GRFs) on knee valgus moments when cutting to these angles. Also, to determine whether sex differences exist in kinematics and kinetics when cutting to 45 and 110 degrees.
Cross-sectional study.
Laboratory setting.
Forty-five (20 females) healthy young adult soccer athletes aged 16 to 23 years.
Kinematic and kinetic variables were compared between randomly cued side-step cutting maneuvers to 45 and 110 degrees. Predictors of knee valgus moment were determined for each task.
Kinematic variables: knee valgus angle, hip abduction, and internal rotation angles. Kinetic variables: vertical, posterior, and lateral GRFs, and knee valgus moment.
Knee valgus moments were greater when cutting to 110 degrees compared with 45 degrees, and females exhibited greater moments than males. Vertical and lateral GRFs, hip internal rotation angle, and knee valgus angle explained 63% of the variance in knee valgus moment during cutting to 45 degrees. During cutting to 110 degrees, posterior GRF, hip internal rotation angle, and knee valgus angle explained 41% of the variance in knee valgus moment.
Cutting tasks with larger redirection demands result in greater knee valgus moments. Similar factors, including shear GRFs, hip internal rotation, and knee valgus position contribute to knee valgus loading during cuts performed to smaller (45 degrees) and larger (110 degrees) angles.
Reducing vertical and shear GRFs during cutting maneuvers may reduce knee valgus moments and thereby potentially reduce risk for anterior cruciate ligament injury.
比较向45度和110度切入时的额状面膝关节力矩,以及与膝关节外翻力矩相关的运动学和动力学,确定向这些角度切入时运动学和地面反作用力(GRFs)对膝关节外翻力矩的预测价值。此外,确定向45度和110度切入时运动学和动力学方面是否存在性别差异。
横断面研究。
实验室环境。
45名(20名女性)年龄在16至23岁的健康年轻成年足球运动员。
比较随机提示的向45度和110度侧步切入动作之间的运动学和动力学变量。确定每项任务中膝关节外翻力矩的预测因素。
运动学变量:膝关节外翻角度、髋关节外展和内旋角度。动力学变量:垂直、向后和侧向GRFs,以及膝关节外翻力矩。
与向45度切入相比,向110度切入时膝关节外翻力矩更大,女性的力矩大于男性。垂直和侧向GRFs、髋关节内旋角度和膝关节外翻角度解释了向45度切入时膝关节外翻力矩63%的变异。向110度切入时,向后GRF、髋关节内旋角度和膝关节外翻角度解释了膝关节外翻力矩41%的变异。
具有更大转向需求的切入任务会导致更大的膝关节外翻力矩。类似的因素,包括剪切GRFs、髋关节内旋和膝关节外翻位置,在向较小(45度)和较大(110度)角度切入时均会导致膝关节外翻负荷。
在切入动作中减少垂直和剪切GRFs可能会降低膝关节外翻力矩,从而潜在地降低前交叉韧带损伤的风险。