两端膨胀自锁髓内钉治疗股骨骨折的生物力学评价

目的 对一种新型无需传统锁钉的两端膨胀自锁髓内钉进行生物力学性能测试和评价. 方法将6对新鲜人股骨尸体标本分为两组,均制备股骨中段横行骨折模型,分别用两端膨胀自锁髓内钉和国产传统交锁髓内钉内固定,并使断端间保留1.5 cm的裂隙.分别对其进行轴向压缩载荷、水平扭转及三点弯曲等生物力学测试,并对相关实验数据进行统计学分析. 结果两端膨胀自锁髓内钉的抗短缩刚度、抗旋转刚度及抗弯曲刚度均略小于传统交锁髓内钉,差异无统计学意义(P>0.05). 结论两端膨胀自锁髓内钉与交锁髓内钉固定效果相当,具有较强抗压、抗弯、抗旋性能,符合生物学固定的要求,有较好的临床推广应用前景.

A biomechanical evaluation of intramedullary expanded serf-locking nail (IESN) in treatment of femoral fractures

Objective To evaluate the biomechanical properties of a new device of internal fixation for femoral fractures, intrameduUary expanded self-locking nail (IESN). Methods Six pairs of cadaveric specimens of fresh adult femur were used to create transverse fracture models of middle femoral shaft. The specimens were randomized into 2 equal groups. Group 1 was fixated with IESN and Group 2 with conventional interlocking nails. A 1.5 cm bone gap was remained between fracture ends. All specimens were subjected to biomechanical tests for axial compression load, horizontal torsion and three-peint bending. The data were analyzed with statistic software SPSS13.0. Results The rigidities of Group 1 resisting rotation, axial displacement and bending were a little lower than those of Group 2, but there were no statistically significant differences between the two groups. Conclusion In treatment of femoral fractures, IESN is nearly as good as conventional interlocking nails but its application is simpler and free of conventional locking.