Study on mechanism of trabecular pattern using microcomputed tomography --development of new theoretical model--

利用显微计算机断层扫描研究小梁模式的机制--新理论模型的发展--

• 批准号: 08457392
• 负责人: MIURA Hiromasa
• 金额: $ 4.8万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08457392/
• 关键词: morphology; trabeculae; microCT; electromagnetic field; remodelling; finite element method; osteoporosis; 有限要素性; バイオメカニクス; フラクタル

Fractal is a mathematical theory developed by Mandelbrot and fractal dimension can be used as an index of complexity of a certain pattern. First, we made it clear that there are significant characteristics of fractal in trabecular bone architecture. Furthermore, in development of microCT, we established the method of fractal dimension as new parameter of complexity of trabecular microarchitecture.Secondly, we investigated the effects of menatetrenone (2-methyl-3-all-trans-tetraprenyl-1, 4-naphthoquinone), a vitamin K2 on 3-D trabecular microarchitecture using an animal model for postmenopausal osteoporosis induced by ovariectomy and a calcium-deficient diet. This study suggests that an 8-week administration of menatetrenone protects against the loss of trabecular bone volume and its connectivity in the osteoporotic rat model, when the treatment is started just after the ovariectomy.Thirdly, in order to investigate morphological changes of the 5th caudal bone in rats' under mechanical loading, the non-invasive and periodic measurements were carried out by using micro CT.The cross-sectional area of the axial or offset loading rat increased up to 25 percent while the increasing rate in the control rat was about 5 percent. The finite element method under the offset loading condition showed more symmetric stress distribution in the offset loading rat than in the axial loading rat and control rat. These results indicated that C5 were adapted to the offset load by remodelling bone architecture.Finally, the study was performed to investigate the effects of externally applied pulsing electromagnetic fields (PEMF) on trabecular conformation in osteoporotic rats. The 3D-reconstructed images and the bone volume density indicated that the externally applied PEMF prevented bone loss at the center of trabeculae in the distal portion of the femur.

分形是由Mandelbrot发展起来的一种数学理论，分形维数可以作为某种图案复杂程度的指标。首先，我们明确了骨小梁结构具有明显的分形特征。在microCT的发展过程中，我们建立了以分形维数作为衡量骨小梁微结构复杂性的新参数。其次，我们采用卵巢切除术和缺钙饮食诱导的绝经后骨质疏松动物模型，研究维生素K2（2-甲基-3-全反式-四异戊二烯基-1，4-萘醌）对骨小梁三维微结构的影响。该研究表明，当在卵巢切除术后立即开始治疗时，给予8周的menatetrenone可以防止骨质疏松大鼠模型中骨小梁体积及其连接性的损失。第三，为了研究大鼠第五尾骨在机械负荷下的形态学变化，使用微型CT进行非侵入性和周期性测量。轴向或偏置载荷大鼠的截面积增加了25%，而对照大鼠的增加率约为5%。偏置加载条件下的有限元分析显示，偏置加载组的应力分布比轴向加载组和对照组更对称。这些结果表明，C5通过重建骨结构来适应偏置载荷。最后，研究了脉冲电磁场（PEMF）对偏置载荷大鼠骨小梁形态的影响。三维重建图像和骨体积密度表明，外部施加的PEMF防止了股骨远端部分骨小梁中心的骨丢失。

项目成果

中西義孝: "骨粗鬆症モデルラットの骨梁形態変化に及ぼすバルス電磁場の効果" 日本臨床バイオメカニクス学会誌. 19. 333-336 (1998)

Yoshitaka Nakanishi：“脉冲电磁场​​对骨质疏松症模型大鼠骨小梁形态变化的影响”日本临床生物力学学会杂志 19. 333-336 (1998)。

Mimura H: "Combination method of rigid body spring model and finite element method for analyzing contact problems." Journal of Japanese Society for Clinical Biomechanics and Related Research. 19. 477-480 (1998)

Mimura H：“刚体弹簧模型与有限元方法相结合分析接触问题。”

三浦裕正: "接触問題に対するFEW単独とRBSM-FEM併用による解法の比較検討" 日本臨床バイオメカニクス学会誌. 19. 477-480 (1998)

Hiromasa Miura：“单独使用 FEW 和结合使用 RBSM-FEM 解决接触问题的解决方案的比较研究”日本临床生物力学学会杂志 19. 477-480 (1998)。

三浦裕正: "変形性膝関節症、変形性脊椎症、骨粗鬆症の相互関連に関する疫学調査." 厚生省長寿科学総合研究平成8年度研究報告書. 4. 192-196 (1997)

Hiromasa Miura：“膝骨关节炎、骨关节炎和骨质疏松症之间相互关系的流行病学调查。”卫生福利部，老年科学综合研究，1996年研究报告4。192-196。

蔵田耕作・日垣秀彦・三浦裕正・馬渡太郎・村上輝夫・岩本幸英: "ラット尾椎の機械的刺激に対する形態リモデリングの非侵襲計測" 第8回バイオエンジニアリング学術講演会夏季セミナー講演論文集. 97・4. 92-93 (1997)

Kosaku Kurata、Hidehiko Higaki、Hiromasa Miura、Taro Mawatari、Teruo Murakami、Yukihide Iwamoto：“大鼠尾椎机械刺激响应的形态重塑的非侵入性测量”第八届生物工程学术会议夏季研讨会论文集97·4。 92-93 (1997)