中国组织工程研究

中国组织工程研究 ›› 2016, Vol. 20 ›› Issue (9): 1295-1301.doi: 10.3969/j.issn.2095-4344.2016.09.012

• 数字化骨科 digital orthopedics • 上一篇    下一篇

钽金属棒置入修复股骨头坏死的三维有限元分析

杨宾宾，刘耀升，刘蜀彬   

  1. 解放军第307医院，北京市 100071
  • 收稿日期:2016-01-26 出版日期:2016-02-19 发布日期:2016-02-19
  • 通讯作者: 刘耀升，博士，副主任医师，解放军第307医院，北京市 100071
  • 作者简介:杨宾宾，男，1990年生，山东省枣庄市人，汉族，解放军军事医学科学院在读硕士，主要从事股骨头坏死方面的研究。
  • 基金资助:
    北京市科委首都临床特色应用研究(z121107001012093)《股骨头坏死钽棒技术适应症优选与个体化治疗技术规范》

     

Necrosis of the femoral head treated by tantalum rod implant: three-dimension finite element analysis

Yang Bin-bin, Liu Yao-sheng, Liu Shu-bin   

  1. the 307 Hospital of PLA, Beijing 100071, China
  • Received:2016-01-26 Online:2016-02-19 Published:2016-02-19
  • Contact: Liu Yao-sheng, M.D., Associate chief physician, the 307 Hospital of PLA, Beijing 100071, China
  • About author:Yang Bin-bin, Studying for master’s degree, the 307 Hospital of PLA, Beijing 100071, China
  • Supported by:

    the Capital Clinical Characteristic Application Research of Beijing Municipal Science and Technology Commission, No. z121107001012093

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被引次数

4

摘要：

文章快速阅读：

文题释义：

股骨头塌陷的力学原理：股骨头坏死病灶的塌陷与生物力学因素有着直接的关系，其主要原因是坏死区应力水平下降、坏骨周围的应力集中，其病理基础是骨小梁微骨折，其实质是一种生物力学不稳，将这种现象称为“头内不稳”。置入钽金属棒可以减少股骨头内的不良应力，稳定股骨头内部结构，尽可能减少股骨头塌陷的发生。

钽金属骨小梁棒：其本身具有一定初始力学强度, 钽棒置入不仅仅是将填充物放入股骨头负重区死骨清除后的骨缺损内, 而是能够尽快地实现与受区周围骨质的整合, 使其与受区一起，共同承担载荷，实现应力的正常分布。多孔钽棒与骨的弹性模量相当，故在股骨头内有相同的应力和应变模式，具有承担生理负荷的能力。

 

背景：髓芯减压以及髓芯减压后钽金属棒置入是当前修复早中期股骨头坏死最常见的方法，可有效控制甚至逆转股骨头坏死进展，但是术后股骨头的力学支撑与疗效对比需要进一步探讨。
目的：运用有限元分析的方法探讨髓芯减压对股骨头机械支撑力的影响及钽金属棒置入修复股骨头缺血性坏死的优势。
方法：选择健康成人右侧股骨头为观察对象，经螺旋CT扫描得各断面图像，输入计算机识别和提取股骨轮廓并行三维重建。按生理状态下股骨头载荷的三维空间分布，股骨远端采用完全固定的设置方式，股骨头上方施加与股骨干呈25°夹角，方向向下的570 N压力。选取股骨头外上方承力区并计算平均塌陷值，对股骨头三维有限元模型进行计算，得到股骨头受力模型在不同坏死范围、不同修复方法治疗前后股骨头负重区表面的塌陷值。

结果与结论：股骨头髓芯减压后的塌陷值明显增大，以负重区最为明显；随着坏死范围的增大股骨头的塌陷值也随之增大；减压后予以多孔钽棒置入后塌陷值明显降低。髓芯减压虽能清除死骨，但减压本身进一步降低了股骨头的力学性能，改变了股骨头原本的结构支撑，髓芯减压基础上以多孔钽金属棒为股骨头及软骨下骨板提供安全而有效的力学支撑，能有效防止塌陷，并为骨组织的修复提供条件。 

ORCID: 0000-0001-7140-8888 (刘耀升)

关键词: 骨科植入物, 数字化骨科, 钽金属棒, 股骨头坏死, 生物力学, 有限元分析

Abstract:

BACKGROUND: Core decompression and tantalum rod implantation after core decompression are common methods to repair early and middle stages of necrosis of femoral head, can effectively control and even reverse the progress of necrosis of the femoral head. Comparison of mechanical support and curative effect of femoral head after operation deserves further investigation.
OBJECTIVE: To explore the effect of core decompression on mechanical pulp femoral head support by using the finite element analysis and the advantages of tantalum implant treatment in the repair of avascular necrosis of the femoral head. 
METHODS: The right femur of healthy adults was chosen as the research object, and CT scanning was conducted to get the images of cross-sections. The images were then inputted into computer to get contour of femur and rebuild three-dimensional model. Distal end of femur was completely fixed, the angle of the top of femoral head and the femoral shaft was 25°, and 570 N pressure on the femoral head was applied according to the three-dimensional space distribution of femur force under physiological state. Three-dimensional finite element models were calculated to get the collapse values in different necrotic areas of the femoral head before and after different repair methods.
RESULTS AND CONCLUSION: After core decompression, collapse values were apparently increased, especially in the weight-bearing area. With increased range of necrosis, collapse values also increased. After core decompression, collapse values decreased obviously after porous tantalum rod implantation. Although core decompression could remove dead bone, decompression itself further reduced the mechanical properties of the femoral head and changed the original femoral head support. On the basis of core decompression, porous tantalum rod provided safe and effective mechanical support for femoral head and subchondral bone plate, could effectively prevent collapse and provide conditions for the restoration of bone tissue.