不同钢板内固定方式治疗髋臼横行骨折的生物力学分析

Biomechanical analysis of different plate internal fixations for acetabular fracture

目的对不同钢板内固定方式治疗髋臼横行骨折的生物力学进行研究。方法将60具新鲜成人半骨盆标本制成髋臼横行骨折模型并随机分成A、B、C、D、E五组,每组各12具标本。采取前柱锁定重建板对A组标本进行固定,后柱锁定重建板对B组标本进行固定,前柱锁定重建板联合后柱拉力螺钉对C组标本进行固定,前柱拉力螺钉联合后柱锁定重建板对D组标本进行固定,双柱拉力螺钉对E组标本进行固定。各组标本在生物力学试验机的作用下分别接受600、1200、1800N载荷,测定各组标本骨折端水平位移及纵向位移距离,计算轴向刚度。结果 C、D、E组标本水平位移、纵向位移距离均显著小于A、B组,差异具有统计学意义(P<0.05);C、D、E组轴向刚度均显著大于A、B组,差异具有统计学意义(P<0.05);A组标本水平位移、纵向位移距离均显著小于B组,差异具有统计学意义(P<0.05);轴向刚度显著大于B组,差异具有统计学意义(P<0.05);C、D、E组间各指标相比,差异无统计学意义(P>0.05)。结论髋臼横行骨折采取双柱固定所获得的稳定性高于单柱固定方式,而不同双柱固定方法所获得的稳定性接近。

Objective To compare the biomechanicals of different plate internal fixations in acetabular fracture. Methods Totally 60 adult fresh semi-pelvis specimens were divided into group A, B, C, D and E random- ly. Group A was fixed by locking reconstruction plates, group B was fixed by locking reconstruction plates, group C was fixed by locking reconstruction plates and the posterior columns with lag screws, group D was fixed by lag screws and the posterior columns with locking reconstruction plates and group E was fixed by lag screws. 600N, 1200N and 1800N loads were imposed on specimens with biomechanical testing machine, and the horizontal displacement, verti- cal displacement and axial stiffness were observed in the 5 groups. Results The horizontal displacement and verti- cal displacement in group C, D and E were lower than those in group A and group B ,and the differences had statisti- cal significance （P 〈 0. 05 ）. The axial stiffness in group C, D and E was significantly higher than that in group A and group B, and the differences had statistical significance （ P 〈 0.05 ）. The horizontal displacement and vertical displacement in group A were significantly lower than those in group B, and the differences had statistical signifi- cance （ P 〈 0. 05 ）. The axial stiffness in group A was significantly higher than that in group B, and the difference had statistical significance （ P 〈 0. 05 ）. There was no significant difference in indexes among group C, D and E （ P 〉0. 05 ）. Conclusion The stability of the acetabular transverse fracture is higher than that of the single column fixation method, and the stabilities among different double column fixation methods are close.