三种内外固定器械固定胫骨骨折的蠕变特性分析

Creep characteristics of tibial fractures with three internal and external fixation devices

背景:模拟胫骨骨折分别以髓内钉、钢板、外固定支架进行固定后的蠕变力学特性罕见报道。目的:分析3种内外固定器械固定胫骨骨折的蠕变特性,为临床提供生物力学参数。方法:模拟胫骨骨折分别以髓内钉、钢板、外固定支架进行固定,在电子万能试验机上对3组标本进行轴向压缩蠕变实验。结果与结论:髓内钉固定组7 200 s蠕变量为0.22%,钢板固定组7 200 s蠕变量为0.34%,外固定支架组7 200 s蠕变量为0.42%。外固定支架固定组7 200 s蠕变量大于钢板固定组和髓内钉固定组(P<0.05),钢板固定组7 200 s蠕变量大于髓内钉固定组(P<0.05)。结果表明外固定支架、钢板固定、髓内钉固定股骨的蠕变特性均发生了改变,但改变程度不同。

BACKGROUND： The creep mechanical properties of tibial fractures after fixation with intramedullary nails, steel plates and external fixation support are rarely reported. OBJECTIVE： To analyze the creep characteristics of tibial fractures with three internal and external fixation devices to provide biomechanical parameters for the clinic. METHODS： We simulated tibial fractures with intramedullary nails, steel plates, and external fixator. We performed axial compression creep tests on three sets of specimens on the electronic universal testing machine. RESULTS AND CONCLUSION： The creep variables of intramedullary nail fixation group were 0.22%, and the creep variables of steel plate fixation group were 0.34% in 7 200 s. In the external fixation group, creep variables were 0.42% in 7 200 s. The creep variables were larger in the external fixation group than in the plate fixation and intramedullary nail fixation groups at 7 200 s（P〈0.05）. The creep deformation was greater in the plate fixation group than that of intramedullary nail fixation group in 7 200 s（P〈0.05）. The results suggested that creep characteristics of the external fixation, plate fixation and intramedullary nail fixation were all changed, but the changes were different.