新型点状接触动力加压接骨板的研制(生物力学部分)

A NEW POINT CONTACT-DYNAMIC COMPRESSION PLATE BIOMECHANICAL EVALUATION

目的:研制一种可对骨折断端动力加压的点状接触接骨板,对其加压特性及固定的力学稳定性进行评价。方法:使用测加压力装置,比较一颗螺钉动力位加压时动力加压钢板及点状接触动力加压接骨板的加压力。使用山羊新鲜配对胫骨20对,做成横断骨折模型,分别用DCP及PC-DCP加压固定和骨折断端存在3mm间隙情况下固定,在多功能力学试验机上进行四点弯曲实验及扭转实验。结果:PC-DCP与DCP之间加压力无显著性差异(p>0.05)。PC-DCP固定的抗弯刚度稍大于DCP,抗扭刚度较DCP稍降低,但两者之间差异均无显著性(p>0.05)。结论:PC-DCP可对骨折断端有效加压,具有与DCP相似的力学稳定性。

To determine the mechanical properties(stiffness)and compression force of a new design of point contact plate,with the ability of dynamic compression for reducing the gap at the fracture site and enhancing the stability.Methods:A device wasused compare the compression force of point contact-dynamic compression plate(PC-DCP)with that of dynamic compression plate(DCP)when a cortical screw was placed at compression position.In20paired fresh cadaveric sheep tibiae,mid-shaft transverse osteotomies were created and fixed with PC-DCPs and DCPs.In10pairs,compression force was applied at the fracture sites.In the other10paires,there was a3-mm gap between the fracture sites.Four point bending and torsion tests were conducted to determine the bend-ing and torsion stiffness.Results:there were no statistically significant differences in compression force between the DCPs and PC-DCPs (p>0.05).Whether there was a bone gap or not,no significant differences in bending and torsion stiffness were seen between the two experimental plates(p>0.05).Conclusion:The PC-DCP can ap-ply a comparable compression force between the fracture gap.Mechanically,the PC-DCP plate has adequate sta-bility in clinical application.