Experimental flatfoot model: The contribution of dynamic loading
Experimental flatfoot model: The contribution of dynamic loading
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DOI：
10.1177/107110070102200309
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发表时间：
2001-03-01
影响因子：
2.7
通讯作者：
Parks, BG
中科院分区：
文献类型：
--
作者：
Chu, IT;Myerson, MS;Parks, BG
本研究的目的是确定肌肉力量的应用（模拟步态的中间部分的动态阶段）是否对扁平足畸形有影响。我们创建了一个扁平足模型，在每七个尸体脚标本抓住跟腱，腓骨长肌，腓骨短肌，屈趾长肌，屈拇长肌腱与软组织虎钳钳通过钢丝绳连接到气缸。实验包括四个阶段：1）初始静态轴向载荷; 2）3，000次载荷循环后的轴向载荷（平均值，735 N;范围，70 - 1400 N）; 3）释放弹簧韧带和足底筋膜后的轴向载荷;以及4）额外3，000次载荷循环后的轴向载荷。在每个阶段，对静态（仅轴向加载）和动态（轴向加载，肌腱张紧，模拟站立中期的肌肉力量）条件进行了X线评价。在实验的前两个阶段，没有观察到静态和动态条件之间的变化。在第三阶段后，变化的第一跖骨的角度和内侧楔骨的高度，特别是在动态条件下。这些和其他放射学变化在第四阶段被放大，但仅在动态条件下。我们的结论是，为了建立一个有效的扁平足模型，内侧结构，包括弹簧韧带和可能的足底筋膜，必须切断。足部的循环载荷进一步增加了足弓的扁平度，并且这种效果被动态载荷放大。
The goal of this study was to determine if the application of muscle forces (simulating the dynamic phase of the midstance part of gait) had an effect on flatfoot deformity. We created a flatfoot model in each of seven cadaver foot specimens by grasping the Achilles, peroneus longus, peroneus brevis, flexor digitorum longus, and flexor hallucis longus tendons with soft-tissue vice clamps connected via wire cables to pneumatic cylinders. The experiment included four stages: 1) initial static axial loading; 2) axial loading after 3,000 load cycles (average, 735 N; range, 70 to 1400 N); 3) axial loading after releasing the spring ligament and plantar fascia; and 4) axial loading after an additional 3,000 load cycles. At each stage, both static (with axial loading only) and dynamic (axial loading with tensioning of the tendons to simulate the muscle forces at midstance) conditions were evaluated radiographically. No change was observed between the static and dynamic conditions in the first two phases of the experiment. After the third phase, changes in the talar-first metatarsal angle and the height of the medial cuneiform were noted, particularly in the dynamic condition. These and additional radiographic changes were magnified in the fourth phase, but only in the dynamic condition. We concluded that, to create an effective flatfoot model, the medial structures, including the spring ligament and possibly the plantar fascia, must be severed. Cyclic loading of the foot further increased the arch flattening, and this effect was magnified by dynamic loading.