【摘要】 目的探讨股骨颈骨折愈合后取出空心加压螺钉遗留钉道不植骨、植骨及正常的股骨头颈部的生物力学特性,为临床提供实验依据。方法收集9付股骨标本测量不同载荷下三组股骨头颈的位移变化,对其结果进行统计学分析。并对股骨头颈三维有限元模型进行测试,得出股骨头颈部的力学特性。结果不植骨组与正常组、植骨组的股骨头颈部载荷—位移均值,在统计学上存在明显性差异(P<0.05);而植骨组与正常组无统计学差异(P>0.05)。有限元模型测量显示不植骨模型的最大应力集中在股骨头负重区,远远大于植骨模型股骨颈下方的内后侧处最大应力集中区。结论钉道内植骨有利于提高股骨头颈部的生物力学性能,预防因股骨头部应力过于集中,导致股骨头坏死塌陷等并发症的发生。更多还原

【Abstract】 Objective To study biomechanical performance of fracture-healing femoral head and neck after the hollow compression screws are taken out in ungrafting-bone group,grafting-bone group,normal group,and provide theoretical basis for the treatment of necrosis of the femoral head by bone grafting in the channel of screws.Methods Nine femurs fixed and preserved by formalin were used in this test.They were randomly divided into three groups: normal group,ungrafting-bone group,grafting-bone group.According to inversed-triangle,at the range of physiological load,it tested the defixed bias-value of three group femoral head at different load.The data were collected and analyzed.The three-dimension finite element model of the femoral head and neck was calculated.Nodal solution of stress value and max-offset was calculated at area of femoral head and neck,then the data were compared and analyzed.Results Compared with the mean of load-offset about the femoral head and neck,biomechanical capability of ungrafting-bone group was lowest with regard to other two groups,the influence was very hard,P <0.05.But there was no singnificant difference between normal group and grafing-bone group,P >0.05.Analysis of the three-dimension finite element model showed that the massive stress was concentrated at weight loading region of ungrafting-bone group’s femoral head,it was an dangerous chance to lead to femoral head collapse.Conclusion For the treatment of femur neck fractures with cannulated compression screws,bone grafting in the channel of screw should be used to improve biomechanical integrity after fracture healed and cannulated compression screws are taken out.This is of benefit to loading in early stage and to preventing the collapse of femoral head,etc.更多还原