环抱式肋骨接骨器内固定处理医源性断肋的生物力学研究

目的 对环抱式肋骨接骨器内固定处理医源性断肋的生物力学进行评价.方法 将新鲜冷冻的15对猪平行肋骨建立断肋模型后,一半采用多孔钢板加螺丝固定,设为多孔钢板加螺丝固定组,另一半采用环抱式肋骨接骨器固定,设为环抱式肋骨接骨器固定组,分别进行三点弯曲试验、扭转试验与疲劳试验,观察两组试验结果.结果 三点弯曲试验中位移2 mm、4 mm、6 mm三个时间点多孔钢板组的施力大小显著大于环抱式肋骨接骨器组,组间比较差异有统计学意义(P<0.05);扭转10°时多孔钢板组扭转力大于环抱式肋骨接骨器组,差异有统计学意义(P<0.05);扭转20°、30°、40°时两组扭转力大小比较差异均无统计学意义(P>0.05).多孔钢板组刚度降低幅度明显大于环抱式肋骨接骨器组,组间比较差异具有统计学意义(P<0.05).结论 环抱式肋骨接骨器内固定处理医源性断肋的生物力学指标整体上较多孔钢板更优,建议在临床进一步推广应用.

Biomechanical study of rib embracing connector for internal fixation of iatrogenic rib fracture

Objective To evaluate the biomechanical features of rib embracing connector for internal fixation of iatrogenic fracture of rib. Methods Models of broken rib were established by 15 pairs of fresh frozen parallel ribs of pig, half of which were treated by porous plate and screw fixation (group A) and the other half were fixed by rib embrac-ing connector (group B). Three-point bending test, torsion test and fatigue test were carried out respectively, and the re-sults of the two groups were observed. Results In three-point bending test, the applied force at displacement of 2 mm, 4 mm, 6 mm in group A was significantly larger than that of group B (P<0.05). In torsion test, the twisting force for tor-sion of 10° was significantly greater in group A than group B (P<0.05), but the twisting force showed no statistically sig-nificant difference between the two groups for torsion of 20° , 30° , 40° (P>0.05). The decrease in stiffness of group A was more significant than that of group B, and the difference between the two groups was statistically significant (P<0.05). Conclusion Rib embracing connector, compared with porous plate, results in better biomechanical indexes in the treatment of iatrogenic rib fracture on the whole, which should be recommended in clinic.