基于跳远运动员起跳动作膝关节损伤风险的生物力学研究

Biomechanical Research on the Risk of Knee Joint Injury Based on Long Jumper Take-Off

采用实验测试和数理统计等研究方法获取跳远起跳动作的转化、应力和角度等运动学与动力学参数,从运动生物力学的视角对跳远运动员在起跳时导致膝关节损伤的因素进行分析。结果表明:(1)跳远运动员在完成起跳动作时,膝关节所承受的压力非常之大,且膝关节此时处于屈曲状态,引起关节中心点发生改变,使膝关节内的半月板产生异常高的扭转与剪切应力;(2)在起跳缓冲和转化阶段,膝关节所受力的方向与身体重心运动方向相反,且膝关节由伸膝到屈膝不能合理地进行缓冲,容易造成膝关节两侧副韧带和十字韧带的损伤;(3)跳远运动员在起跳时受到的冲击力与身体重心的速度以及作用时间有着密切的关系;(4)跳远运动员在起跳时受到地面垂直与侧向的反作用力对膝关节容易造成损伤;(5)膝关节的变化量大,转动惯量就大,稳定性变弱,同时屈膝导致髌骨与接触面减小,容易造成膝关节损伤。

The kinematics and dynamics parameters of long jump take-off movement,such as transformation,stress and angle,were obtained by experimental test and mathematical statistics.From the point of view of Sports Biomechanics,the paper analyzes the factors of knee joint injury of long jumpers during take-off.The results show that firstly the pressure on the knee joint is very great when long jumpers complete take-off,and the knee joint is in flexion state at this time,which causes the change of the central point of the joint.And the knee produces abnormally high torsion and shear stress in the meniscus.Secondly,during the buffering and transition phases of take-off,the force on the knee joint is in the opposite direction of the motion of the body center of gravity,so the knee joint cannot be buffered reasonably from extension to flexion,which easily causes the injuries of collateral ligament and cruciate ligament on both sides of the knee joint.Thirdly,the impact force on the long jumper during the take-off is closely related to the velocity of the center of gravity of the body and the time of the action.Fourthly,the knee joint is damaged by the vertical and lateral counterforces of the long jumpers during the take-off.Lastly,the greater the knee joint changes,the greater the inertia of rotation is and weaker the stabilitis.And bending the knee decreases patella and the contact surface to make it easy to cause knee joint injury.