Louw Quinette, Grimmer Karen, Vaughan Christopher
Department of Physiotherapy, Stellenbosch University, P O Box 19063, Tygerberg, 7505, South Africa.
BMC Musculoskelet Disord. 2006 Mar 7;7:22. doi: 10.1186/1471-2474-7-22.
A common knee injury mechanism sustained during basketball is landing badly from a jump. Landing is a complex task and requires good coordination, dynamic muscle control and flexibility. For adolescents whose coordination and motor control has not fully matured, landing badly from a jump can present a significant risk for injury. There is currently limited biomechanical information regarding the lower limb kinetics of adolescents when jumping, specifically regarding jump kinematics comparing injured with uninjured adolescents. This study reports on an investigation of biomechanical differences in landing patterns of uninjured and injured adolescent basketball players.
A matched case-control study design was employed. Twenty-two basketball players aged 14-16 years participated in the study: eleven previously knee-injured and eleven uninjured players matched with cases for age, gender, weight, height and years of play, and playing for the same club. Six high-speed, three-dimensional Vicon 370 cameras (120 Hz), Vicon biomechanical software and SAS Version 8 software were employed to analyse landing patterns when subjects performed a "jump shot". Linear correlations determined functional relationships between the biomechanical performance of lower limb joints, and paired t-tests determined differences between the normalised peak biomechanical parameters.
The average peak vertical ground reaction forces between the cases and controls were similar. The average peak ground reaction forces between the cases and controls were moderately correlated (r = -0.47). The control (uninjured) players had significantly greater hip and knee flexion angles and significantly greater eccentric activity on landing than the uninjured cases (p < 0.01).
The findings of the study indicate that players with a history of knee injuries had biomechanically compromised landing techniques when compared with uninjured players matched for gender, age and club. Descriptions (norms) of expected levels of knee control, proprioceptive acuity and eccentric strength relative to landing from a jump, at different ages and physical developmental stages, would assist clinicians and coaches to identify players with inappropriate knee performance comparable to their age or developmental stage.
篮球运动中常见的一种膝关节损伤机制是从跳跃中落地姿势不佳。落地是一项复杂的动作，需要良好的协调性、动态肌肉控制能力和灵活性。对于协调性和运动控制能力尚未完全成熟的青少年来说，从跳跃中落地姿势不佳会带来较大的受伤风险。目前，关于青少年跳跃时下肢动力学的生物力学信息有限，尤其是关于受伤青少年与未受伤青少年跳跃运动学的比较。本研究报告了一项关于未受伤和受伤青少年篮球运动员落地模式生物力学差异的调查。
采用配对病例对照研究设计。22名年龄在14至16岁的篮球运动员参与了该研究：11名曾有膝关节损伤的运动员和11名未受伤的运动员，后者在年龄、性别、体重、身高、比赛年限以及所属俱乐部方面与病例组相匹配。使用6台高速三维Vicon 370摄像机（120赫兹）、Vicon生物力学软件和SAS 8.0软件来分析受试者进行“跳投”时的落地模式。线性相关性确定了下肢关节生物力学性能之间的功能关系，配对t检验确定了标准化峰值生物力学参数之间的差异。
病例组和对照组的平均垂直地面反作用力峰值相似。病例组和对照组的平均地面反作用力峰值呈中度相关（r = -0.47）。对照组（未受伤）运动员在落地时的髋关节和膝关节屈曲角度明显更大，离心活动也明显更强，与受伤病例组相比差异有统计学意义（p < 0.01）。
该研究结果表明，与在性别年龄和俱乐部方面相匹配的未受伤运动员相比，有膝关节损伤史的运动员在生物力学上的落地技术存在缺陷。针对不同年龄和身体发育阶段，描述从跳跃中落地时预期的膝关节控制水平、本体感觉敏锐度和离心力量（标准），将有助于临床医生和教练识别出膝关节表现与其年龄或发育阶段不相称的运动员。
