【摘要】 目的比较交锁髓内钉在治疗胫骨远端骨折时不使用阻挡钉、使用1枚阻挡钉、使用2枚阻挡钉3种条件下的生物力学稳定性。方法将8具国人新鲜尸体的双侧胫骨制成胫骨远端骨折模型,每具尸体的左右侧胫骨随机分成A、B 2组。其中A组截骨平面位于踝关节平面上方7 cm,用以模拟低位胫骨远端骨折,能使用2枚冠状面锁钉的骨折类型;B组截骨平面位于踝关节平面上方5 cm,用以模拟极低位胫骨远端骨折,仅能使用1枚冠状面锁钉的骨折类型。A、B 2组均在不使用阻挡钉、使用1枚阻挡钉、使用2枚阻挡钉3种条件下进行生物力学稳定性测试。结果在A组实验中,不使用阻挡钉、使用1枚阻挡钉、使用2枚阻挡钉之间位移明显,差异有统计学意义(P<0.05);在B组测试中,不使用阻挡钉与使用1枚阻挡钉时位移差异无统计学意义(P>0.05),但使用1枚和2枚阻挡钉时位移差异有统计学意义(P<0.05)。结论在A组类型骨折中使用交锁髓内钉,可以结合阻挡钉以显著提高内固定的稳定性;在B组类型骨折中使用交锁髓内钉,必须使用2枚阻挡钉方可在一定程度上改善内固定的稳定性,但与A组相比,总体稳定性明显变差,如在临床中确需使用,需加用恰当的外固定或采用改良型交锁髓内钉。更多还原

【Abstract】 Objective To compare the biomechanical stability under the three conditions of using no blocking screw,a blocking screw,two blocking screws at the treatment of distal tibial fractures with intramedullary nails.Methods The double side tibia of 8 fresh cadaver were used to establish tibia distal fracture model,and the left side and right side of each cadaver were divided randomly into A,and B group,the osteotomy plane of group A was located above 7 cm of ankle joint plane to simulate low tibia distal fracture which was the type using 2 coronal plane screws;the osteotomy plane of group B was located above 5 cm of ankle joint plane to simulate extremely low tibia distal fracture which was the type that could only use 1coronal plane screws.Both group A and B were tested with the biomechanical study under the conditions of using no blocking screw,a blocking screw,two blocking screws.Results In group A,there were significant statistical differences between the conditions of using no blocking screw,a blocking screw and two blocking screws(P <0.05);while in group B,there was no significant statistical difference between the conditions of using no blocking screw and a blocking screw(P >0.05),but it showed significantly statistical differences between the conditions of using a blocking screw and two blocking screws(P <0.05).Conclusion When intramedullary nails are used in group A to treat this kind of fracture,the blocking screws are combined to significantly improve the stability of internal fixation;while intramedullary nails are used in group B to treat this kind of fracture,more than 2 blocking screws should be used to improve the stability of fixation in an certain extent but if compared group B with A,its overall stability is obviously bad.If the method must be used in clinic it should be combined with appropriate of external fixation or with the improved type of intramedullary nails.更多还原