人胫骨四种内固定器的生物力学评价

Biomechanical evaluation of four internal fixation instruments in human tibia fracture

目的 :比较四种内固定器在人胫骨骨折时的生物力学特性。方法 :将经防腐固定成人胫骨9根 ,制成中段横断骨折 ,依次安放双Ender钉 ,双矩形钉 ,梅花钉和四孔钢板 ,并进行前内侧和前外侧三点弯曲实验及轴向扭转实验。结果 :Ender钉、四孔钢板、梅花钉和矩形钉内固定器的三点弯曲刚度分别为 :前外侧 13 .0、2 5 .4、41.8、2 3 .3N/mm ;前内侧 2 5 .5、 16.2、41.4、2 0 .2N/mm ;轴向扭转 15°时的力矩分别为 :1.43、4.67、0 .86、0 .86Nm。梅花钉抗弯曲较其它内固定器强 (P <0 .0 1～ 0 .0 5 ) ,余者间无显著性差别 ;四孔钢板抗轴向扭转较其它内固定器强 (P <0 .0 1) ,Ender钉次之。结论 :4种内固定器中四孔钢板抗轴向扭转性能最好 ,梅花钉的三点弯曲刚度最强 ,对于胫骨骨折 ,Ender钉和矩形钉可以提供较好的稳定作用。

Objective:To compare the biomechanical properties of four internal fixation instruments in tibia fracture.Methods:The transverse fracture was produced at the middle of tibia on 9 embedded adult cadaveric tibia.The three bending test and axial torsion test were conducted on each specimens after the fracture been fixed by Ender nail,rectangle shaped nail,quincunx shaped nail and four hole plate separately.Results:The anti bending character of quincunx shaped nail fixed tibia is significantly higher than those of other instruments ( P <0.01 or 0.05).The anti torsion character of four hole plate fixed tibia is much higher than those of other instruments ( P <0.01).Conclusion:Four hole plate provides the strongest torsion fixation and quincunx shaped nail provides the strongest bending fixation.