[钛镍形状记忆锯齿臂环抱接骨板的生物力学评价及其对骨折愈合的影响]

[Biomechanical evaluation of TiNi shape-memory sawtooth-arm embracing plate and its effect on fracture healing].

作者信息

Yan Xuegang, Bao Tongzhu, Zhao Weidong, Yan Fei, Liang Dongzhu, Ding Zhibing

机构信息

The First College of Clinical Medical Science, Three Gorges University, Yichang Hubei, 443003, P.R. China.

出版信息

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010 Feb;24(2):219-22.

PMID:20187457

Abstract

OBJECTIVE

To investigate the detailed biomechanics of TiNi shape-memory sawtooth-arm embracing plate (TiNi SMA) by comparing with limited-contact dynamic compression plate (LC-DCP) and static interlocking intramedullary nail (SIiN), so as to provide theoretical evidence for clinical application.

METHODS

Eight paired cadaveric femurs immersed in formaldehyde were harvested from eight specimens of adults. After making X-ray films and modeling midpiece transverse fracture, one side randomly was fixed by TiNi SMA (group A) and SIiN (group C) orderly, the other side was fixed by LC-DCP (group B). The axial compression, three-point bending (pressed from plate side and opposite side both of group A and group B, from inside of group C), and torsion were tested, and the stress shielding rate was compared.

RESULTS

At every classified axial compression load, the strains of group A were greater than those of group B and group C (P < 0.05), the displacements of group A were greater than those of group B and group C (P < 0.05) except 100 N. At every classified three-point bending moment, the displacement of group A were greater than those of group B and group C pressed both from two sides, but there was no difference when pressing from two sides under the same load of group A (P > 0.05). At every torsion moment, the torsion angels of group A were greater than those of group B (P < 0.05), but equal to those of group C (P > 0.05). At 600 N of axial compression load, the stress shielding rates of groups A, B, C were 48.30% +/- 22.99%, 89.21% +/- 8.97%, 95.00% +/- 3.15%, respectively, group A was significantly less than group B and group C (P < 0.01).

CONCLUSION

The anti-bending ability of TiNi SMA is weaker than LC-DCP and SIiN; the anti-torsion ability of TiNi SMA is weaker than SIiN, but TiNi SMA is a center-type internal fixation, the superior stress shielding rate and micromovement promote the stress stimulation of fracture, which makes it an ideal internal fixation device.

摘要

目的

通过与有限接触动力加压钢板（LC-DCP）及静力交锁髓内钉（SIiN）比较，探讨镍钛形状记忆锯齿臂环抱接骨板（TiNi SMA）详细的生物力学性能，为临床应用提供理论依据。

方法

从8具成年尸体标本中获取浸泡在甲醛中的8对尸体股骨。拍摄X线片并制作中段横行骨折模型后，一侧随机先后用TiNi SMA（A组）和SIiN（C组）固定，另一侧用LC-DCP（B组）固定。测试轴向压缩、三点弯曲（A组和B组从钢板侧和对侧加压，C组从髓内加压）及扭转性能，并比较应力遮挡率。

结果

在各级轴向压缩载荷下，A组的应变均大于B组和C组（P<0.05），除100 N外，A组的位移均大于B组和C组（P<0.05）。在各级三点弯曲力矩下，A组从两侧加压时的位移均大于B组和C组，但在A组相同载荷下从两侧加压时无差异（P>0.05）。在各级扭转力矩下，A组的扭转角度大于B组（P<0.05），但与C组相等（P>0.05）。在600 N轴向压缩载荷下，A、B、C组的应力遮挡率分别为48.30%±22.99%、89.21%±8.97%、95.00%±3.15%，A组明显小于B组和C组（P<0.01）。