Regional Variations in Shear Strength and Density of the Human Thoracic Vertebral Endplate and Trabecular Bone
Regional Variations in Shear Strength and Density of the Human Thoracic Vertebral Endplate and Trabecular Bone
复制标题
人类胸椎终板和骨小梁的剪切强度和密度的区域差异
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
S. Saha
中科院分区：
文献类型：
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作者：
F. Xavier;J. Jauregui;N. Cornish;Rebecca Jason;D. Chatterjee;G. Feuer;W. Hayes;B. Kapadia;J. Carter;H. Yoshihara;S. Saha
背景以前的研究调查了椎体的整体机械强度;然而，关于椎体终板和松质骨内不同区域的生物力学特性的信息有限。此外，还没有研究机械强度和各种密度测量之间的相关性。方法取15具成人尸体脊柱标本（平均年龄77岁），解剖T10椎体。从每个椎体制备12个7.2 mm（直径）× 3.2 mm（高度）的圆柱形芯。使用不锈钢管状刀片产生剪切，并用来自机械试验机的测力传感器测量。在机械测试之前计算光学密度和堆积密度。测试后测量表观密度、材料密度和灰分密度。结果终板和松质骨的材料密度和剪切强度均由前向外侧逐渐增大。前区终板剪切强度（0.52 ± 0.08 MPa）显著低于外侧区（2.72 ± 0.59 MPa）（p=0.017）。与前部（2 ± 0.60 N）相比，外侧（12 ± 2.74 N）（p=0.09）和中部（10 ± 2.24 N）（p=0.2）的小梁骨最大承载能力分别高出5倍和4.5倍。机械强度与灰分密度呈正相关，与材料密度的相关性更大。结论终板和松质骨的抗剪强度均是前区最低，外侧区最高。材料密度与机械强度的相关性最好。较新的脊柱植入物可以优化终板和松质骨外侧的载荷，以减少螺钉松动和椎间盘置换器械下沉的可能性。本研究由SUNY Downstate Medical Center IRB委员会审查; IRB#：533603-2。
Background Previous studies investigated the overall mechanical strength of the vertebral body; however, limited information is available on the biomechanical properties of different regions within the vertebral endplate and cancellous bone. In addition, the correlation between mechanical strength and various density measurements has not been studied yet. Methods Thoracic (T10) vertebrae were harvested from fifteen human cadaveric spines (average age: 77 years old). Twelve cylindrical cores of 7.2 mm (diameter) by 3.2 mm (height) were prepared from each vertebral body. Shear was produced using a stainless steel tubular blade and measured with a load cell from a mechanical testing machine. Optical and bulk densities were calculated before mechanical testing. Apparent, material, and ash densities were measured after testing. Results Material density and shear strength increased from anterior to lateral regions of both endplate and cancellous bone. Endplate shear strength was significantly lower in the anterior (0.52 ± 0.08 MPa) than in the lateral region (2.72 ± 0.59 MPa) (p=0.017). Trabecular bone maximum load carrying capacity was 5 times higher in the lateral (12 ± 2.74 N) (p=0.09) and 4.5 times higher in the central (10 ± 2.24 N) (p=0.2) than in the anterior (2 ± 0.60 N) regions. Mechanical strength positively correlated with ash density, and even moreso with material density. Conclusion Shear strength was the lowest at the anterior region and highest at the lateral region for both endplate and cancellous bone. Material density had the best correlation with mechanical strength. Newer spinal implants could optimize the loading in the lateral aspects of both endplate and cancellous bone to reduce the likelihood of screw loosening and the subsidence of disc replacement devices. This study was reviewed by the SUNY Downstate Medical Center IRB Committee; IRB#: 533603-2.
影响因子：
2.4
作者：
GOULET, RW;GOLDSTEIN, SA;FELDKAMP, LA
通讯作者：
FELDKAMP, LA