Wallace B J, Kernozek T W, Bothwell E C
Department of Health Professions, University of Wisconsin-La Crosse, La Crosse, WI, USA.
J Sports Med Phys Fitness. 2007 Dec;47(4):377-84.
Females experience at least twice as many non-contact anterior cruciate ligament (ACL) injuries as males. The aim of this study was to investigate if males and females exhibited different characteristics while performing a modified pro-agility test.
Collegiate Division III male baseball (n=14) and female softball (n=13) players performed 4 trials of a modified pro-agility task, which consisted of running toward a force platform target for 5 steps, planting their right foot, and propelling themselves off of the target with their left foot. Kinematic and kinetic parameters were compared using a multivariate analysis of variance between gender with the level of significance set at P<0.05.
Males and females exhibited similar knee valgus angles. Females had a greater maximum knee extension angle (10.14 degrees vs 17.43 degrees ), and greater knee range of motion (46.12 degrees vs 40.12 degrees ). Both groups reached maximum knee flexion at 52% of stance. Females had significantly more maximum hip flexion than males (28.86 degrees vs 22.75 degrees ). Females had significantly smaller minimum internal knee varus moments than their male counterparts (1.12 Nm/kg vs 1.55 Nm/kg). Vertical ground reaction forces as a percentage of bodyweight, and stance time, were not statistically different. The female group displayed an external knee rotation angle (2.49 degrees ) during the beginning of their stance, which was significantly different than the internal rotation angle (4.11 degrees ) in the male group. Early in stance knee rotation angle was highly correlated with the lack of internal knee varus moment (males R(2)=0.75, females R(2)=0.88).
Females displayed knee moments and kinematics that may place them at greater risk for ACL injury during a stop-cut task. Females should be coached to perform stop cuts with more knee flexion and a more neutral knee rotation angle upon foot contact in an effort to reduce moments that may place the ACL at risk.
女性非接触性前交叉韧带（ACL）损伤的发生率至少是男性的两倍。本研究的目的是调查男性和女性在进行改良敏捷性测试时是否表现出不同的特征。
大学三年级男子棒球运动员（n = 14）和女子垒球运动员（n = 13）进行4次改良敏捷性任务试验，该任务包括朝着力平台目标跑5步，用右脚着地，然后用左脚从目标上蹬离。使用多变量方差分析比较性别之间的运动学和动力学参数，显著性水平设定为P<0.05。
男性和女性表现出相似的膝外翻角度。女性的最大膝关节伸展角度更大（10.14度对17.43度），膝关节活动范围更大（46.12度对40.12度）。两组在站立52%时达到最大膝关节屈曲。女性的最大髋关节屈曲明显多于男性（28.86度对22.75度）。女性的最小膝关节内翻力矩明显小于男性（1.12 Nm/kg对1.55 Nm/kg）。垂直地面反作用力占体重的百分比和站立时间在统计学上没有差异。女性组在站立开始时表现出膝关节外旋角度（2.49度），这与男性组的内旋角度（4.11度）有显著差异。站立初期膝关节旋转角度与膝关节内翻力矩的缺乏高度相关（男性R(2)=0.75，女性R(2)=0.88）。
女性在急停变向任务中表现出的膝关节力矩和运动学特征可能使她们面临更高的ACL损伤风险。应指导女性在急停变向时增加膝关节屈曲，并在脚着地时保持更中立的膝关节旋转角度，以减少可能使ACL处于危险中的力矩。
