Geometrical variations in white and gray matter affect the biomechanics of spinal cord injuries more than the arachnoid space
Geometrical variations in white and gray matter affect the biomechanics of spinal cord injuries more than the arachnoid space
复制标题
DOI：
10.1177/1687814016664703
复制
发表时间：
2016-08-01
影响因子：
2.1
通讯作者：
Petit, Yvan
中科院分区：
文献类型：
--
作者：
Fradet, Leo;Arnoux, Pierre-Jean;Petit, Yvan
创伤性脊髓挫伤导致生活质量下降，但其病理机制尚未完全了解。先前的研究强调了脑脊液在脊髓保护中的作用。然而，目前尚不清楚脑脊液的贡献相对于其他因素（如白色/灰质比例）的重要性。脊髓和周围的形态特征的有限元模型被用来研究脊髓挫伤的机制，考虑蛛网膜下腔和白色/灰质的比例。两个椎体节段（T6和L1）以4.5ms（-1）横向撞击，这证明了三个主要结果：而脑脊液的存在在脊髓保护中起着重要的作用（压缩百分比降低高达19%），蛛网膜间隙变化沿着脊柱似乎具有有限的（3%压缩减少）的影响。从腰椎到胸椎水平的白色和灰质几何形状的差异使胸椎水平的脊髓压缩减少高达14%。脊髓矢状面的应力分布与中央脊髓综合征一致，脊髓前角的局部应力集中被脑脊液的存在大大减少。使用精细的脊髓有限元方法表明，所有的几何参数参与脊髓挫伤机制。因此，脊髓损伤的标准必须考虑在每个椎体水平。
Traumatic spinal cord contusions lead to loss of quality of life, but their pathomechanisms are not fully understood. Previous studies have underlined the contribution of the cerebrospinal fluid in spinal cord protection. However, it remains unclear how important the contribution of the cerebrospinal fluid is relative to other factors such as the white/gray matter ratio. A finite element model of the spinal cord and surrounding morphologic features was used to investigate the spinal cord contusion mechanisms, considering subarachnoid space and white/gray matter ratio. Two vertebral segments (T6 and L1) were impacted transversely at 4.5ms(-1), which demonstrated three major results:While the presence of cerebrospinal fluid plays a significant contributory role in spinal cord protection (compression percentage decreased by up to 19%), the arachnoid space variation along the spine appears to have a limited (3% compression decrease) impact.Differences in the white and gray matter geometries from lumbar to thoracic spine levels decrease spinal cord compression by up to 14% at the thoracic level.Stress distribution in the sagittal spinal cord section was consistent with central cord syndrome, and local stress concentration on the anterior part of the spinal cord being highly reduced by the presence of cerebrospinal fluid.The use of a refined spinal cord finite element method showed that all the geometrical parameters are involved in the spinal cord contusion mechanisms. Hence, spinal cord injury criteria must be considered at each vertebral level.