Abstract：
BACKGROUND: The proximal regions of the brachial plexus (roots, trunks) are more susceptible to permanent damage due to stretch injuries than the distal regions (cords, terminal branches). A better description of brachial plexus mechanical behavior is necessary to better understand deformation mechanisms in stretch injury. The purpose of this study was to model the biomechanical behavior of each portion of the brachial plexus (roots, trunks, cords, peripheral nerves) in a cadaveric model and report differences in elastic modulus, maximum stress and maximum strain.
METHODS: Eight cadaveric plexi, divided into 47 segments according to regions of interest, underwent cyclical uniaxial tensile tests, using a BOSE® Electroforce® 3330 and INSTRON® 5969 material testing machines, to obtain the stress and strain histories of each specimen. Maximum stress, maximum strain and elastic modulus were extracted from the load-displacement and stress-strain curves. Statistical analyses used 1-way ANOVA with post-hoc Tukey HSD (Honestly Significant Difference) and Mann-Whitney tests.
RESULTS: Mean elastic modulus was 8.65 MPa for roots, 8.82 MPa for trunks, 22.44 MPa for cords, and 26.43 MPa for peripheral nerves. Differences in elastic modulus and in maximum stress were statistically significant (p < 0.001) between proximal (roots, trunks) and distal (cords, peripheral nerves) specimens.
CONCLUSIONS: Proximal structures demonstrated significantly smaller elastic modulus and maximum stress than distal structures. These data confirm the greater fragility of proximal regions of the brachial plexus.
METHODS: Eight cadaveric plexi, divided into 47 segments according to regions of interest, underwent cyclical uniaxial tensile tests, using a BOSE® Electroforce® 3330 and INSTRON® 5969 material testing machines, to obtain the stress and strain histories of each specimen. Maximum stress, maximum strain and elastic modulus were extracted from the load-displacement and stress-strain curves. Statistical analyses used 1-way ANOVA with post-hoc Tukey HSD (Honestly Significant Difference) and Mann-Whitney tests.
RESULTS: Mean elastic modulus was 8.65 MPa for roots, 8.82 MPa for trunks, 22.44 MPa for cords, and 26.43 MPa for peripheral nerves. Differences in elastic modulus and in maximum stress were statistically significant (p < 0.001) between proximal (roots, trunks) and distal (cords, peripheral nerves) specimens.
CONCLUSIONS: Proximal structures demonstrated significantly smaller elastic modulus and maximum stress than distal structures. These data confirm the greater fragility of proximal regions of the brachial plexus.
摘要：
背景：臂丛神经的近端区域（根，树干)比远端区域(绳索，终端分支机构)。为了更好地了解拉伸损伤中的变形机制，有必要更好地描述臂丛的力学行为。这项研究的目的是对臂丛神经各部分的生物力学行为进行建模（根，树干,绳索,周围神经)在尸体模型中，并报告弹性模量的差异，最大应力和最大应变。
方法：八个尸体丛，根据感兴趣的区域分为47个片段，进行了周期性单轴拉伸试验，使用BOSE®Electroforce®3330和INSTRON®5969材料测试机，获得每个试样的应力和应变历史。最大应力,从载荷-位移和应力-应变曲线中提取最大应变和弹性模量。统计分析使用单向ANOVA和事后TukeyHSD(诚实显著差异)和Mann-Whitney检验。
结果：根的平均弹性模量为8.65MPa，干线为8.82MPa，帘线为22.44MPa，周围神经为26.43MPa。弹性模量和最大应力的差异在近端(根，树干)和远端(绳索，周围神经）标本。
结论：近端结构的弹性模量和最大应力明显小于远端结构。这些数据证实了臂丛神经近端区域的更大脆性。
方法：八个尸体丛，根据感兴趣的区域分为47个片段，进行了周期性单轴拉伸试验，使用BOSE®Electroforce®3330和INSTRON®5969材料测试机，获得每个试样的应力和应变历史。最大应力,从载荷-位移和应力-应变曲线中提取最大应变和弹性模量。统计分析使用单向ANOVA和事后TukeyHSD(诚实显著差异)和Mann-Whitney检验。
结果：根的平均弹性模量为8.65MPa，干线为8.82MPa，帘线为22.44MPa，周围神经为26.43MPa。弹性模量和最大应力的差异在近端(根，树干)和远端(绳索，周围神经）标本。
结论：近端结构的弹性模量和最大应力明显小于远端结构。这些数据证实了臂丛神经近端区域的更大脆性。
