三种内固定方式固定骶髂关节骨折脱位的生物力学比较研究

The Biomechanicai Study on Three Different Kinds of Fixation for the Impaired Sacroiliac Joint

目的比较骶髂关节(SIJ)行三种不同内固定后对其生物力学稳定性的影响.方法取成年男性防腐骨盆标本12个,随机分为4组.A组为正常完整的骨盆标本(N),作为对照组;B组为SIJ使用重建钢板(SP)内固定组;C组为SIJ使用骶髂螺钉(SS)内固定组;D组为SIJ使用ISOLA内固定组.用实验应力的方法测试各组的生物力学稳定性.结果 (1)ISOLA应变最小;(2)负载500N,ISOLA位移最小;(3)强度测定:ISOLA与N相差4%(P>0.05),SS和SP与N相差分别为16%、21%(P<0.05);(4)轴向刚度和弯曲刚度比较,ISOLA高于SS11%、8%,高于SP15%、13%.统计显示ISOLA无明显差异(P>0.05),而SS和SP却呈现统计学意义(P<0.05);(5)骨盆的极限力学性能测试,ISOLA的承载能力与N相差为9%(P>0.05),SS和SP与N相差分别为31%、36%(P<0.05).结论 ISOLA明显比SS和SP优越,ISOLA、SS、SP三种不同的内固定可以维持骨折脱位后的SIJ的稳定,以ISOLA固定最为坚固.

Objective To compare the stability of the three different kinds of fixation for the sacroiliac joint.Methods Twelve embalmed male pelves were harvestd for this study.According to fixation ways,they were divided into four groups randomly：N,SP,SS and ISOLA.Nondestructive biomechanical tests were performed in axis compression on every group.Results（1）ISOLA strained the smallest.（1）Loaded with 500N,ISOLA displaced the smallest.（2）The strength of ISOLA decreased 4% compared with N（P〉0.05）.The strength of SS decreased 16%,SP decreased 21%（P〈0.05）.（3）The axial stiffenes and bend stiffenes of ISOLA increased 11%,8% compared with SS,increased 15%,13% compared with SP.ISOLA showed no the significant difference（P〉0.05）.But SS and SP showed the significant difference（P〈0.05）.（5）The pelvise＇s extreme mechanical function,ISOLA decreased 9% compared with N（P〉0.05）.SS and SP decreased 31%,36%（P〈0.05）.The results indicated SS and SP were inferior to ISOLA.Conclusion ISOLA,SS and SP can maintain the stability of the impaired sacroiliac joint,and ISOLA is the stongest.