Neuromuscular and Rehabilitation Robotics Laboratory (NeuRRo Lab), Department of Physical Medicine and Rehabilitation, Michigan Medicine, University of Michigan, Ann Arbor, Michigan.
Department of Biomedical Engineering, Wayne State University, Detroit, Michigan.
Sports Health. 2023 May;15(3):372-381. doi: 10.1177/19417381221104042. Epub 2022 Jun 29.
Quadriceps weakness is common after anterior cruciate ligament (ACL) reconstruction and can alter gait mechanics. Functional resistance training (FRT) is a novel approach to retraining strength after injury, but it is unclear how it alters gait mechanics. Therefore, we tested how 3 different types of FRT devices: a knee brace resisting extension (unidirectional brace), a knee brace resisting extension and flexion (bidirectional brace), and an elastic band pulling backwards on the ankle (elastic band)-acutely alter gait kinetics in this population.
The type of FRT device will affect ground-reaction forces (GRFs) during and after the training. Specifically, the uni- and bidirectional braces will increase GRFs when compared with the elastic band.
Crossover study.
Level 2.
A total of 15 individuals with ACL reconstruction received FRT with each device over 3 separate randomized sessions. During training, participants walked on a treadmill while performing a tracking task with visual feedback. Sessions contained 5 training trials (180 seconds each) with rest between. Vertical and anterior-posterior GRFs were assessed on the ACL-reconstructed leg before, during, and after training. Changes in GRFs were compared across devices using 1-dimensional statistical parametric mapping.
Resistance applied via bidirectional brace acutely increased gait kinetics during terminal stance/pre-swing (ie, push-off), while resistance applied via elastic band acutely increased gait kinetics during initial contact/loading (ie, braking). Both braces behaved similarly, but the unidirectional brace was less effective for increasing push-off GRFs.
FRT after ACL reconstruction can acutely alter gait kinetics during training. Devices can be applied to selectively alter gait kinetics. However, the long-term effects of FRT after ACL reconstruction with these devices are still unknown.
FRT may be applied to alter gait kinetics of the involved limb after ACL reconstruction, depending on the device used.
前交叉韧带（ACL）重建后常发生股四头肌无力，可改变步态力学。功能性抗阻训练（FRT）是一种损伤后重新训练力量的新方法，但尚不清楚其如何改变步态力学。因此，我们测试了 3 种不同类型的 FRT 设备：一种抵抗伸展的膝关节支具（单向支具）、一种抵抗伸展和屈曲的膝关节支具（双向支具）以及一个向后拉脚踝的弹性带（弹性带）——在该人群中急性改变步态动力学。
FRT 设备的类型将影响训练期间和训练后的地面反作用力（GRF）。具体来说，与弹性带相比，单向和双向支具会增加 GRF。
交叉研究。
2 级。
共有 15 名 ACL 重建患者在 3 个单独的随机疗程中接受了每种设备的 FRT。在训练过程中，参与者在跑步机上行走，同时进行视觉反馈的跟踪任务。每个疗程包含 5 次训练试验（每次 180 秒），其间休息。在训练前、训练中和训练后评估 ACL 重建腿的垂直和前后 GRF。使用 1 维统计参数映射比较设备之间的 GRF 变化。
双向支具施加的阻力在终末期站立/预摆动（即蹬离）期间急性增加步态动力学，而弹性带施加的阻力在初始接触/加载（即制动）期间急性增加步态动力学。两种支具的行为相似，但单向支具增加蹬离 GRF 的效果较差。
ACL 重建后 FRT 可在训练期间急性改变步态动力学。可以应用设备有选择地改变步态动力学。然而，这些设备在 ACL 重建后进行 FRT 的长期效果仍不清楚。
FRT 可用于改变 ACL 重建后患肢的步态动力学，具体取决于所使用的设备。
