The axial injury tolerance of the human foot/ankle complex and the effect of Achilles tension
The axial injury tolerance of the human foot/ankle complex and the effect of Achilles tension
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DOI：
10.1115/1.1514675
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发表时间：
2002-12-01
影响因子：
1.7
通讯作者：
Eppinger, RH
中科院分区：
文献类型：
--
作者：
Funk, JR;Crandall, JR;Eppinger, RH
足踝复合体的轴向负荷是车辆伤的重要损伤机制，是导致跟骨和胫骨Pilon骨折等严重损伤的原因。在撞击前支撑过程中，通过跟腱施加主动肌肉张力，可在腿部外部、通过趾板和/或踏板施加轴向载荷，也可以在内部施加轴向载荷。本研究的目的是研究跟腱张力对骨折模式的影响，并经验性地模拟足踝复合体的轴向负荷耐力。钝性轴向冲击试验是在有和没有实验模拟跟腱张力的情况下进行的。两组主要骨折方式均为跟骨骨折。然而，随着跟腱张力的增加，胫骨远端骨折更频繁(p<；0。05)。安装在骨骼上的声学传感器表明，骨折是在局部轴力达到峰值时开始的。使用威布尔回归模型对损伤数据集进行生存分析，样本年龄、性别、体重和跟腱张力峰值作为预测变量(R-2=0.90)。建立了一个闭合形式的幸存者函数，根据胫骨轴向力来预测足踝复合体骨折的风险。与50%损伤风险相关的胫骨轴向力从65岁第5百分位数女性的3.7kN到45岁第50百分位数男性的8.3kN，假设没有跟腱张力。本文提出的幸存者函数可用于根据拟人测试装置测量的胫骨最大轴向力来估计钝性轴向撞击对人体造成的足部/脚踝骨折的风险。
Axial loading of the foot/ankle complex is an important injury mechanism in vehicular trauma that is responsible for severe injuries such as calcaneal and tibial pilon fractures. Axial loading may be applied to the leg externally, by the toepan and/or pedals, as well as internally, by active muscle tension applied through the Achilles tendon during pre-impact bracing. The objectives of this study were to investigate the effect of Achilles tension on fracture mode and to empirically model the axial loading tolerance of the foot/ankle complex. Blunt axial impact tests were performed on forty-three (43) isolated lower extremities with and without experimentally simulated Achilles tension. The primary fracture mode was calcaneal fracture in both groups. However fracture initiated at the distal tibia more frequently with the addition of Achilles tension (p < 0. 05). Acoustic sensors mounted to the bone demonstrated that fracture initiated at the time of peak local axial force. A survival analysis was performed on the injury data set using a Weibull regression model with specimen age, gender body mass, and peak Achilles tension as predictor variables (R-2 = 0.90). A closed-form survivor function was developed to predict the risk of fracture to the foot/ankle complex in terms of axial tibial force. The axial tibial force associated with a 50% risk of injury ranged from 3.7 kN for a 65 year-old 5(th) percentile female to 8.3 kN for a 45 year-old 50(th) percentile male, assuming no Achilles tension. The survivor function presented here may be used to estimate the risk of foot/ankle fracture that a blunt axial impact would pose to a human based on the peak tibial axial force measured by an anthropomorphic test device.