股骨横断骨折2种带锁髓内钉固定的力学分析

目的分析自设计动力型带锁髓内钉和目前常用静力型带锁髓内钉固定股骨横断骨折的力学特点.方法将动力型带锁髓内钉和意大利产Orthofix静力型带锁髓内钉分别固定股骨横断骨折后进行力学实验比较.结果 (1)静力型固定股骨横断骨折由于产生应力遮挡,折端缺乏足够的应力刺激,容易导致骨折延迟愈合或不愈合,早期负重锁钉疲劳性断钉的可能大;(2)动力型固定股骨横断骨折完全无应力遮挡,折端形成动力加压作用而促进骨折愈合.结论股骨横断骨折为动力型带锁髓内钉首选的适应症.

Biomechanics characteristics of femoral fracture transverse fixed by dynamic or static interlocking intramedullary nails

Objective To analyse biomechanics characteristics of using dynamic interlocking intramedullary nails designed by ourselves and static interlocking intramedullary nails now in common used separately to fix transverse femoral fracture.Methods To conduct a biomechanics test contrast among transverse femoral fractures fixed by the dynamic or static interlocking intramedullary nails made by Orthofix Italy.Results (1)Femoral transverse fracture fixed by static nails because of stress shielding,fracture surfaces are short of sufficient stress stimulation,it is liable to cause fracture delayed union or nonunion,and caues locking nails fatigue broken if weighted in early phase after operation;(2)That fixed by dynamic fixation without stress shielding completely,it enable fracture surface have dynamic compress and accelerate the femoral fracture union.Conclusion Transverse femoral fracture is the best indications that fixed by dynamic interlocking intramedullary nail.