两种不同固定方式对累及后内侧柱的胫骨平台复杂骨折的生物力学研究

Biomechanics research of two different fixation methods on complex tibial plateau fracture involving tibial plateau posteromedial column

目的:研究后内侧支撑板加外侧"Raft"锁定板内固定和外侧"T"形接骨板固定的累及后内侧柱的胫骨平台复杂骨折的生物力学。方法:选取28具新鲜的尸体(由我市医学院提供),均为成年男性,于尸体中取胫骨上端及股骨下端作为本研究的骨性标本。参考Kelly法制作符合本研究要求的累及后内侧柱的胫骨骨折模型共28具。将所有模型随机分为A、B两组。A组14具,行内侧支撑板加外侧"Raft"锁定板内固定法;B组14例,行外侧"T"形接骨板固定法。使用传感器检查并比较两组骨性标本模型相应位置的转矩变化、水平剪切刚度、轴向刚度、载荷-位移等指标,讨论两种不同固定方式的生物力学。结果:A组模型的平均载荷–位移为(0.07±0.01)mm,B组为(0.12±0.03)mm,A组的平均载荷–位移明显低于B组,差异具有统计学意义(P<0.05);A组的平均轴向刚度为(3 157±346)N/mm,B组为(2 683±253)N/mm,A组的平均轴向刚度明显高于B组,差异具有统计学意义(P<0.05);A组的平均水平剪切刚度为(2 165±217)(N·m)/Deg,B组为(1 593±142)(N·m)/Deg,A组的平均水平剪切刚度明显高于B组,差异具有统计学意义(P<0.05);A组的平均转矩变化为(1.9 3±0.2 1)N·m,B组为(1.5 2±0.1 4)N·m,A组的平均转矩变化明显高于B组,差异具有统计学意义(P<0.0 5)。结论:在累及后内侧柱的胫骨平台复杂骨折的治疗中,采用后内侧支撑板加外侧"Raft"锁定板内固定,较单一的外侧"T"形接骨板固定而言,在生物力学方面的稳定性更高。

Objective： To explore the biodynamics study of supporting board at the inner side and the outer side of the “Raft” locking plate fixation and lateral “T” shaped plate fixation on complex tibial plateau fracture involving tibial plateau posteromedial column. Methods： 28 fresh bodies （provided by the city medical college） were selected, the upper and the lower end of the tibia of the femur were taken as the bone specimens of the study. Total of 28 models of complex tibial plateau fracture involving tibial plateau posteromedial column in accordance with the requirements of this study were made due to Kelly method. All models were randomly divided into group A and group B. Group A had 14 models, using supporting board at the inner side and the outer side of the fracture involving tibial plateau posterome models, using lateral “T” shaped plate fixation. The changes of torque, stiffness of horizontal shear, axial stiffness and load displacement of the two groups were examined and compared, and the biodynamics of two different fixation methods were discussed. Results： The average load of displacement in group A was （0.07±0.01） mm, group B was （0.12±0.03） mm, the average load of displacement in group A was significantly lower than that in group B, the difference was statistically significant （P〈0.05）; the average axial stiffness in group A was （3 157±346） N/mm, group B was （2 683±253） N/mm, the average axial stiffness in group A was significantly higher than that in group B, the difference was statistically significant （P〈0.05）; the average stiffness of horizontal shear in group A was （2 165±217） N·m/Deg, B group （1 593±142） N·m/Deg, the average stiffness of horizontal shear in group A was significantly higher than group B, the difference was statistically significant （P〈0.05）; the average torque changes in group A was （1.93±0.21） N·m, group B was （1.52±0.14） N·m, the average torque change in group A was significantly higher than group B, the difference was statistically significant （P〈0.05）. Conclusion： In the treatment of complex tibial plateau fracture involving tibial plateau posteromedial column, the biomechanical stability of supporting board at the inner side and the outer side of the “Raft” locking plate fixation were better than the single lateral “T” shaped plate fixation.