髋臼四边体骨折3种内固定方式的生物力学评价

目的　探究髋臼四边体骨折的最优内固定方式。 方法　采用半骨盆标本制作髋臼四边体骨折模型12具，按内固定方式随机分成3组，A组：骨盆缘下重建接骨板，B组：骨盆缘下锁定重建接骨板，C组：前柱重建接骨板结合方形区螺钉。将柳叶状压敏片贴于股骨头上，通过垂直加载依次测量生理体重600 N下完整髋臼I组（未制作骨折线）和A、B、C 3组的臼顶接触特性，及连续分级负载下A、B、C 3组的水平位移和纵向位移。 结果 生理体重600 N下3组内固定的髋臼负重区接触特性未能恢复至正常，负重面积、平均应力、峰值应力及分级载荷下水平位移和纵向位移均存在统计学差异（P<0.05，200 N除外），且水平位移和纵向位移都随载荷的增加而增大，而在1800 N时A组纵向位移达到失效标准。 结论 对髋臼四边体骨折予以3种不同内固定，前柱重建接骨板结合方形区螺钉内固定的稳定性及接触特性均优于骨盆缘下接骨板内固定，可以减少创伤性关节炎的发生率。

Biomechanical evaluation of three kinds of internal fixation methods for acetabular quadrilateral area fracture

Objective　The purpose of this study was to evaluate the best internal fixation methods of acetabular quadrilateral area fracture. Methods The quadrilateral area fracture models were created by 12 males hemipelves specimens, divided into three groups randomly. The fractures were treated respectively with the following internal fixaction methods, infrapectineal buttress reconstruction plate (group A), infrapectineal buttress locking compression plate (group B), reconstruction plate combined with trans-plate quadrilateral screws(group C). Then the willow leaf films were stuck on the femoral head and vertical compressing loading was continued via the fracture models, followed by measurement of physiological weight 600 N on intact acetabulum in group I(No fracture line was made) and internal fixation of acetabular dome contact characteristics and horizontal and vertical displacements in A, B, C groups. Results Under physiological weight of 600 N, acetabular dome contact characteristics in three groups failed to return to normal, There was a significant difference on the loading area, the mean pressure, the peak pressure, horizontal displacements and longitudinal displacements among groups (P<0.05，besides 200 N). With loads increasing, horizontal displacements and longitudinal displacements were larger，and under 1800 N the longitudinal displacements of group A reached failure criteria.　Conclusions　For the acetabular quadrilateral area fracture, the internal fixation stability and contact characteristic of reconstruction plate combined with trans-plate quadrilateral screw metho is w better than infrapectineal buttress plate, and it can reduce incidence rate of traumatic arthritis.