新型骶髂拉力钉力学性能评价

Evaluation of Mechanical Properties of a Novel Sacroiliac Lag Screw

目的研究一种具有螺旋刀片结构新型骶髂拉力钉的生物力学性能。方法用临床中常用的骶髂经皮拉力钉作为对照。使用聚氨酯材料模拟松质骨,利用Instron力学试验机测试对比抗拔出性能。然后使用骨盆标本,以正常骨盆、单侧骶髂关节损伤骨盆、骶髂经皮拉力钉-单钉修复、骶髂经皮拉力钉-双钉修复骶髂关节损伤为对照,分析新型骶髂拉力钉修复正常站立姿态骶髂关节损伤的静态刚度和动态稳定性。结果新型骶髂拉力钉组拉力钉拔出后的聚氨酯材料破坏更小。新型骶髂拉力钉抗拔出的有效把持位移显著大于骶髂经皮拉力钉(P<0.05)。但骶髂经皮拉力的最大抗拔出力显著大于新型骶髂拉力钉(P<0.05)。骶髂关节损伤修复后,采用1枚骶髂新型骶髂拉力钉刚度显著高于骶髂经皮拉力钉-双钉修复组(P<0.05)。骶髂关节损伤组的位移振幅最大,其次为正常组;其余组别的位移振幅较为接近,但差异具有统计学意义(P<0.05)。新型骶髂拉力钉修复的动态稳定性最优,略优于骶髂经皮拉力钉-双钉修复组,骶髂关节损伤组的稳定性最差。新型骶髂拉力钉能有效修复骶髂关节损伤。结论骶髂新型骶髂拉力钉能更有效地把持松质骨,具有一定的临床实用性。

Objective To investigate the biomechanical properties of a novel sacroiliac lag screw with a spiral blade.Methods Percutaneous sacroiliac lag screws were used as the controls.Polyurethane material was used to simulate the trabecular bone,and the pullout resistance performance was tested on an Instron mechanical testing machine.Subsequently,pelvic specimens were utilized to analyze the static stiffness and dynamic stability of the novel sacroiliac lag screw in repairing sacroiliac joint injuries under normal standing conditions,with normal pelvis,single-sided sacroiliac joint injury pelvis,percutaneous sacroiliac lag screw-single screw repair,and percutaneous sacroiliac lag screw-double screw repair as controls.Results The damage to the polyurethane material after screw extraction was smaller in the novel sacroiliac lag screw group.The average effective holding displacement of the novel sacroiliac lag screw was significantly greater than that of the percutaneous sacroiliac lag screw(P<0.05).However,the maximum resistance to the pullout force for the percutaneous sacroiliac lag screw was significantly higher than that for the novel sacroiliac lag screw(P<0.05).The stiffness after repair of sacroiliac joint injuries was significantly higher when using a single sacroiliac lag screw than when using two percutaneous sacroiliac lag screws(P<0.05).The displacement amplitude was the highest in the sacroiliac joint injury group,followed by that in the normal group.The displacement amplitudes in the other groups were similar;however,the differences were statistically significant(P<0.05).The dynamic stability of the sacroiliac lag screw repair group was the best,slightly better than that of the percutaneous sacroiliac lag screw-double screw repair group,and the dynamic stability of the sacroiliac joint injury group was the worst.The novel sacroiliac lag screw effectively repaired the sacroiliac joint injuries.Conclusions The novel sacroiliac lag screw can effectively hold the trabecular bone and has practical clinical utility.