J Sports Sci Med. 2010 Sep 1;9(3):472-9. eCollection 2010.
The purpose of this study is to investigate the alterations of kinetic characteristics in the step up/over test in patients with acute and chronic anterior cruciate ligament (ACL) deficiency. Twenty acute, twenty chronic ACL-deficient (ACLD) patients, and forty healthy controls participated in this study. The step up/over test was performed on a clinical force platform system to obtain the following variables: movement time, lift-up index and impact index. The percentages of the indexes from the stepping leg and time of step-up and swing- over were further calculated. These variables were examined statistically by using mixed repeated measure analysis of variance to reveal the differences between groups and between limbs. Smaller lift-up forces and longer swing-over time in both ACLD groups than those in the control group were found. One exception was the lift-up index in the affected side condition of the acute ACLD group, which was not significantly different from the controls. A reduced contribution to the impact index from the affected stepping leg was also found in the acute ACLD group. The acute ACLD group showed no significant change in their step-up strategy at the affected limbs, but they may have a poorer eccentric control of the affected knees on the step and thus put a larger portion of loading onto the unaffected landing leg. Our results indicated the lift-up index, swing-over time and load- distributing strategy at impact may be important parameters in monitoring functional recovery in patients with ACL deficiency. The detected alterations in these parameters could be used as a reference to design proper rehabilitation exercises for these patients. Key pointsThe lift-up index and the time of swing-over could be important parameters for indentifying functional impairments in patients with ACL deficiency.The differences between limbs were found only in the acute ACLD group with a larger lift-up index and smaller load-distribution at impact on the affected limb.The step up/over test on the clinical force platform system could be helpful in providing a reference to design proper rehabilitation exercise and to monitor the recovery of the functional ability in patients with ACL deficiency.
本研究旨在探讨急性和慢性前交叉韧带（ACL）缺失患者在跨步/过顶测试中运动学特征的变化。二十名急性 ACL 缺失（ACLD）患者、二十名慢性 ACLD 患者和四十名健康对照者参与了本研究。在临床测力平台系统上进行跨步/过顶测试，以获得运动时间、抬腿指数和冲击指数等变量。进一步计算了从踏足腿和上步及过顶时间获得的各指数的百分比。采用混合重复测量方差分析对这些变量进行统计学检验，以揭示组间和肢体间的差异。发现 ACLD 组的抬腿力较小，跨步和过顶时间较长。急性 ACLD 组患侧的抬腿指数与对照组无显著差异，这是唯一的例外。还发现急性 ACLD 组患侧对冲击指数的贡献减少。急性 ACLD 组在患侧的上步策略没有明显变化，但在跨步时对患膝的离心控制可能较差，因此将更大的负荷分配到未受影响的落地腿上。研究结果表明，抬腿指数、过顶时间和冲击时的负荷分配策略可能是监测 ACL 缺失患者功能恢复的重要参数。这些参数的改变可作为设计 ACL 缺失患者康复运动的参考。关键点抬腿指数和过顶时间可能是识别 ACL 缺失患者功能障碍的重要参数。仅在急性 ACLD 组发现了肢体间的差异，患侧的抬腿指数较大，冲击时的负荷分配较小。临床测力平台系统上的跨步/过顶测试有助于为设计适当的康复运动和监测 ACL 缺失患者的功能恢复提供参考。
