有限元分析探索三种内固定模式固定骨质疏松患者股骨转子下螺旋形骨折的生物力学效应  

Biomechanical effects of three internal fixation modes on femoral subtrochanteric spiral fractures in osteoporotic patients by finite element analysis

作　　者：安玉章 蒋电明[1] AN Yuzhang;JIANG Dianming(Department of Orthopaedics,the First Affiliated Hospital of Chongqing Medical University,Chongqing,400010,P.R.China)

机构地区：[1]重庆医科大学附属第一医院骨科,重庆400010

出　　处：《中国修复重建外科杂志》2023年第6期688-693,共6页Chinese Journal of Reparative and Reconstructive Surgery

基　　金：国家自然科学基金面上项目(81472057);重庆市技术创新与应用发展专项面上项目(cstc2020jscx-msxmX0219)。

摘　　要：目的采用有限元技术对比分析3种内固定模式固定骨质疏松患者股骨转子下螺旋形骨折的生物力学效应,为优化内固定模式提供依据。方法纳入10例因外伤致股骨转子下螺旋形骨折的女性骨质疏松患者作为研究对象,年龄65~75岁,身高160~170 cm,体质量60~70 kg。使用螺旋CT对其股骨进行扫描并通过数字化技术建立股骨三维模型,仿真构建采用近端髓内钉(proximal intramedullary nail,PFN)、股骨近端锁定钢板(proximal femoral locking plate,PFLP)以及二者结合(PFLP+PFN)3种内固定模式的计算机辅助设计模型。然后于股骨头处施加相同载荷500 N,比较分析3种内固定模式下内固定器应力分布、股骨应力分布及骨折固定后股骨整体位移情况,从而对其固定效果进行评估。结果PFLP固定模式下钢板应力主要集中在主钉道,钢板各处应力不均等,由头端至尾端逐渐降低;PFN固定模式下应力集中于PFN外侧中段靠上;PFLP+PFN固定模式下,钢板最大应力出现在下段第1、2颗螺钉之间,PFN出现在中段外侧处。PFLP+PFN固定模式钢板最大应力较PFLP固定模式显著升高,而PFN最大应力较PFN固定模式显著降低,差异均有统计学意义(P<0.05)。PFLP、PFN固定模式下,股骨最大应力均出现在股骨中段、最下面1颗螺钉下侧的内外侧皮质骨处;PFLP+PFN固定模式下,股骨应力集中于股骨中段内外侧。3种内固定模式下股骨最大应力差异均无统计学意义(P>0.05)。3种内固定模式固定股骨转子下骨折后均在股骨头处出现最大位移。PFLP固定模式下股骨整体最大位移最大,PFN固定模式次之,PFLP+PFN固定模式最小,差异均有统计学意义(P<0.05)。结论在静态受力情况下,PFLP+PFN固定模式相对于单一PFN和PFLP固定模式产生股骨整体最大位移最小,但其钢板最大应力大于单一PFLP固定模式,提示组合方式虽然具备更高稳定性,但钢板负荷更大,出现固定失效的可能性�Objective The biomechanical characteristics of three internal fixation modes for femoral subtrochanteric spiral fracture in osteoporotic patients were compared and analyzed by finite element technology,so as to provide the basis for the optimization of fixation methods for femoral subtrochanteric spiral fracture.Methods Ten female patients with osteoporosis and femoral subtrochanteric spiral fractures caused by trauma,aged 65-75 years old,with a height of 160-170 cm and a body weight mass of 60-70 kg,were selected as the study subjects.The femur was scanned by spiral CT and a three-dimensional model of the femur was established by digital technology.The computer aided design models of proximal intramedullary nail(PFN),proximal femoral locking plate(PFLP),and the combination of the two(PFLP+PFN)were constructed under the condition of subtrochanteric fracture.Then the same load of 500 N was applied to the femoral head,and the stress distribution of the internal fixators,the stress distribution of the femur,and the displacement of femur after fracture fixation were compared and analyzed under the three finite element internal fixation modes,so as to evaluate the fixation effect.Results In the PFLP fixation mode,the stress of the plate was mainly concentrated in the main screw channel,the stresses of the different part of the plate were not equal,and gradually decreased from the head to the tail.In the PFN fixation mode,the stress was concentrated in the upper part of the lateral middle segment.In the PFLP+PFN fixation mode,the maximum stress appeared between the first and the second screws in the lower segment,and the maximum stress appeared in the lateral part of the middle segment of the PFN.The maximum stress of PFLP+PFN fixation mode was significantly higher than that of PFLP fixation mode,but significantly lower than that of PFN fixation mode(P<0.05).In PFLP and PFN fixation modes,the maximum stress of femur appeared in the medial and lateral cortical bone of the middle femur and the lower side of the lowest sc

关 键 词：骨质疏松 股骨转子下螺旋形骨折 内固定 有限元分析 生物力学 

分 类 号：R687.3[医药卫生—骨科学]