Mechanical analysis of the distal tibia posterior locking plate fixation for posterior Pilon fracture / 中国组织工程研究

ABSTRACT

BACKGROUND:Open reduction and internal fixation has been confirmed to treat posterior Pilon fracture,but choosing which fixation scheme is still under discussion.OBJECTIVE:To explore the biomechanical properties of posterior Pilon fracture after repaired by two different fixation methods,thus providing reference for selecting an appropriate fixation scheme.METHODS:Twenty right artificial femurs were randomized into two groups A and B,and the models of posterior Pilon fracture were established based on its characters and classification.The group A received with 5 holes distal tibial posterior locking plate fixation,and the group B underwent two 3.5 mm of cortical screws from back to front bicortical fixation,followed by placed in the InstronElectroPulsE3000 universal electronic static and dynamic materials testing systems,vertical speed loaded until internal fixation failure,the loading was recorded when different steps appeared.RESULTS AND CONCLUSION:(1) After loading,none of groups presented with screw bent or broken.(2) The axial load when appeared with 0.5,1.0,1.5,and 2.0 mm steps in the group A was higher than that in the group B,and the axial load significantly increased with fracture fragment displacement increasing (P ＜ 0.05).(3) The biomechanical test shows that the distal tibial posterior locking plate fixation is better than screws in the treatment of posterior Pilon fracture.