前十字韧带重建篮球运动员跳起着地动作时下肢动作特征

Feat ure of Lower Extremity Movements during Jumping-landing of Basketball Players after Anterior Cruciate Ligament Reconstruction

为探讨前十字韧带重建术后运动员在完成起跳着地动作时的下肢动作特征,本研究选择10名前十字韧带重建后篮球运动员为重建组,年龄(22.5±0.8)岁,身高(190.3±8.5)cm,体重(85.7±11.3)kg,术后时间(23.3±16.8)月,另外招募10名与其性别、年龄、身高、体重与运动项目配对为对照组,进行跳起后单脚着地平衡的测验;利用十台Vicon红外线摄影机(200Hz)和8枚无线肌电电极(1000Hz)同步收集生物力学参数;使用无母数分析比较重建组与对照组的差异。结果发现,重建组臀中肌与股直肌的肌肉预收缩RMS-EMG活化高于对照组,其数值分别为5.3%、3.2%。重建组在着地瞬间会运用较多的膝关节屈曲,以较为屈曲的方式着地;着地后膝关节活动范围小且关节运动时间短;推蹬期的腓肠肌与胫前肌RMS-EMG活化高于对照组,其数值分别为1.7%、8.3%。本研究的结果说明,重建组着地前以臀中肌与股直肌的肌肉预收缩作为着地瞬间髋与膝关节的稳定机制;在着地瞬间以膝关节较多屈曲的方式着地并缩短关节运动时间降低不稳定状态;推蹬期以腓肠肌与胫前肌作为稳定踝关节的重要策略。本研究成果可用于评估十字韧带重建后运动员的下肢神经肌肉能力是否已恢复到原有的运动水平,并且找出不足的地方或之间的差异,用以降低二次伤害发生的可能性。

The aim of this study was to investigate the characteristics of lower extremity movements in athletes after anterior cruciate ligament reconstruction during jumping-landing. Ten basketball players after anterior cruciate ligament reconstruction were selected as reconstruction group, who were (22.5±0.8) years old, (170.3±8.5) cm of height, (65.7±11.3) kg of body weight and the time since surgery was (23.3±16.8) months. Another ten participants with the same at gender, age, height, weight and sport items were selected as the control group. Participants were asked to perform a double-leg jump followed with a single-leg landing to test the balance. Ten Vicon infrared video cameras (200 Hz), and eight wireless EMG sensors (1000 Hz) were synchronized to acquire the biomechanical parameters. Nonparametric test (Mann-Whitney U test) was used to analyze the differences between reconstruction group and control group. It was found that the levels of RMS-EMG activation of gluteus medius and rectus femoris in reconstruction group were higher than that in control group, which were 5.3% and 3.2% respectively. Knee flexion was much more observed in reconstruction group at the moment of landing and landed in a more buckling way; the movement range of the knee joint was small and the joint movement time was short after landing; and during propulsion phase, greater RMS-EMG activation levels gastrocnemius and activations were found compared to the control group, which were 1.7% and 8.3% respectively. The results in this study indicated that the reconstruction group utilized the muscle pre-contraction of gluteus medius and rectus femoris muscle as the stability mechanism of hips and knees during landing period. Greater knee flexion angles and less movement time were adopted by the reconstruction group to reduce the instability at the moment of landing. Gastrocnemius and anterior tibial muscles were activated as the important strategy to help stabilize the ankle during propulsion phase. The result of this study could be used to assess whether the neuromuscular abilities of the lower extremities of the athletes after cruciate ligament reconstruction have returned to the original level of exercise, and to identify deficiencies or differences in order to prevent the possibility of secondary injury.