数字散斑法测量加载200N与500N股骨干骨折钢板固定下的位移

Digital Speckle Measuring of Bias on the Steel Pltae of Femoral Fractures with 200 and 500 Newton

目的数字散斑法测试钢板螺钉的位移,为临床上分析螺钉断裂之原因提供理论依据。材料与方法取6根成人防腐股骨标本,于股骨干中点横行锯断,制造股骨干中段骨折模型。将骨折标本进行复位并使用10孔钢板加压固定,骨折线两端各使用5枚螺丝钉固定。设计成10种状态进行对比测量锁钉位移,分别是:a.模拟骨折愈合后的受力状态(钢板固定后,未锯断);b.骨折后加压钢板坚强内固定组;c.在b组基础上近端去一枚螺丝钉;d.在c组基础上远端去一枚螺丝钉;e.在d组基础上近端去一枚螺丝钉;f.在e组基础上远端去一枚螺丝钉;g.在f组基础上近端去一枚螺丝钉;h.在g组基础上远端去一枚螺丝钉;i.在h组的基础上近端去一枚螺丝钉;j.在i组基础上远端去一枚螺丝钉。在200 N、500N(牛顿)拉力下,电子万能试验机加载测量,相关软件计算位移。结果(1)螺丝钉1与10、2与9、3与8、4与7、5与6的比较差异无统计学意义(P>0.05),其余两两比较差异有统计学意义(P<0.05)。结论应选择6孔以上的钢板,以减少由于钢板的强度损失所引发的螺钉断裂。

Objective The bias of the steel plate＇s nail were measured method, a theoretical basis was provided for clinical fracture. Methods of by the digital speckle 6 femoral specimen were taken. The steel plate fixation model in the femur 1/2 was made. Ten conditions were designed sim- ulating to compare the experimental model： a. the femur was not sawed with the compression steel plate fixed （integrity, simulation of the cured fracture）; b. the internal fixation of compression steel plates（segmentation）; c. a proximal screw was removed based on b; d. a distal screw was removed based on c; e. a proximal screw was removed based on d; f. a distal screw was removed based on e; g. a proximal screw was removed based on f; h. a distal screw was removed based on g~ i. a proximal screw was removed based on h; j. a distal screw was removed based on i. Then the specimens were fixed and installed on electronic universal testing machine. Under the Rally of 200N and 500N（newton）, the bias were calculated by the related software. Results There was no significance between screw 1 and 10.2 and 9.3 and 8,4 and 7,5 and 6（P〉0. 05） ,and the left were significant（P〈0. 05）. Conelutions When the steel plate for the treatment of femoral shaft fracture is used, more than six pores of steel plate should be chosen to reduce its stability loss avoid leading to the breakage of screws.