Nagano Yasuharu, Ida Hirofumi, Akai Masami, Fukubayashi Toru
Department of Health and Sports, Niigata University of Health and Welfare, Niigata, Japan.
Sports Med Arthrosc Rehabil Ther Technol. 2011 Jul 14;3(1):14. doi: 10.1186/1758-2555-3-14.
Some research studies have investigated the effects of anterior cruciate ligament (ACL) injury prevention programs on knee kinematics during landing tasks; however the results were different among the studies. Even though tibial rotation is usually observed at the time of ACL injury, the effects of training programs for knee kinematics in the horizontal plane have not yet been analyzed. The purpose of this study was to determine the effects of a jump and balance training program on knee kinematics including tibial rotation as well as on electromyography of the quadriceps and hamstrings in female athletes.
Eight female basketball athletes participated in the experiment. All subjects performed a single limb landing at three different times: the initial test, five weeks later, and one week after completing training. The jump and balance training program lasted for five weeks. Knee kinematics and simultaneous electromyography of the rectus femoris and Hamstrings before training were compared with those measured after completing the training program.
After training, regarding the position of the knee at foot contact, the knee flexion angle for the Post-training trial (mean (SE): 24.4 (2.1) deg) was significantly larger than that for the Pre-training trial (19.3 (2.5) deg) (p < 0.01). The absolute change during landing in knee flexion for the Post-training trial (40.2 (1.9) deg) was significantly larger than that for the Pre-training trial (34.3 (2.5) deg) (p < 0.001). Tibial rotation and the knee varus/valgus angle were not significantly different after training. A significant increase was also found in the activity of the hamstrings 50 ms before foot contact (p < 0.05).
The jump and balance training program successfully increased knee flexion and hamstring activity of female athletes during landing, and has the possibility of producing partial effects to avoid the characteristic knee position observed in ACL injury, thereby preventing injury. However, the expected changes in frontal and transverse kinematics of the knee were not observed.
一些研究调查了前交叉韧带（ACL）损伤预防计划对着陆任务期间膝关节运动学的影响；然而，研究结果各不相同。尽管在ACL损伤时通常会观察到胫骨旋转，但尚未分析针对水平面膝关节运动学的训练计划的效果。本研究的目的是确定跳跃和平衡训练计划对女性运动员膝关节运动学（包括胫骨旋转）以及股四头肌和腘绳肌肌电图的影响。
八名女性篮球运动员参与了实验。所有受试者在三个不同时间进行单腿着陆：初始测试、五周后以及完成训练一周后。跳跃和平衡训练计划持续了五周。将训练前的膝关节运动学以及股直肌和腘绳肌的同步肌电图与完成训练计划后测量的结果进行比较。
训练后，关于足部接触时膝关节的位置，训练后试验的膝关节屈曲角度（平均值（标准误）：24.4（2.1）度）显著大于训练前试验（19.3（2.5）度）（p < 0.01）。训练后试验着陆期间膝关节屈曲的绝对变化（40.2（1.9）度）显著大于训练前试验（34.3（2.5）度）（p < 0.001）。训练后胫骨旋转和膝关节内翻/外翻角度无显著差异。在足部接触前50毫秒时，腘绳肌的活动也显著增加（p < 0.05）。
跳跃和平衡训练计划成功增加了女性运动员着陆期间的膝关节屈曲和腘绳肌活动，并且有可能产生部分效果以避免ACL损伤中观察到的典型膝关节位置，从而预防损伤。然而，未观察到膝关节在额状面和横断面上预期的运动学变化。
