髋关节表面置换术中股骨头缺损区骨水泥填充和空置两种处理方法的生物力学比较  

Biomechanical comparison of bone-cement filling and cement vacancy treatments for femoral head defect in hip resurfacing arthroplasty

作　　者：何志勇[1] 李明[1] 陶崑[1] 方超华[1] 章军辉[1] 狄正林[1] 

机构地区：[1]浙江省宁波市第六医院关节外科,315040

出　　处：《中华关节外科杂志（电子版）》2014年第5期54-58,共5页Chinese Journal of Joint Surgery(Electronic Edition)

基　　金：浙江省宁波市科技局C50-社会发展科研项目(201201C5010001)

摘　　要：目的运用三维有限元的方法比较髋关节表面置换术中股骨头缺损区填充骨水泥和空置后的生物力学变化,探讨术中股骨头缺损区可靠的处理方法。方法采用CT扫描获得正常股骨图像数据,重建正常股骨三维有限元模型,建立缺损区直径为股骨头直径50%和80%的两个股骨模型,采用计算机辅助技术按标准手术技术装配假体模型,对缺损区采用骨水泥填充和空置两种处理方式,建立四个不同的股骨头坏死行髋关节表面置换术有限元模型。对模型施加模拟站立位应力,分析和比较股骨头和颈部各区峰值应力和等效应变。结果股骨头内应力变化:50%股骨头直径缺损组,填充模型股骨头各区应力集中不明显,空置模型股骨头近端1区内应力集中明显;80%股骨头直径缺损组,填充模型股骨头各区的应力集中在1区超过100%,2区内则低于100%,空置模型1区内应力集中都超过1000%,2区内S2区达766.89%为最高。股骨颈内应力变化:50%直径缺损组填充和空置模型股骨颈各区应力集中在±50%以内;80%股骨头直径缺损组填充模型颈部各区应力集中在±50%以内,空置模型的各区峰值应力集中明显。股骨头等效应变:50%直径缺损组填充模型头内各区变化不明显,空置模型头内近端增加明显。80%直径缺损组填充模型头内近端1区等效应变增加率有两个区块明显增高;而空置模型的等效应变增加率急剧增高。股骨颈的等效应变:50%直径缺损组填充和空置模型颈部各区变化不明显,80%直径缺损组填充模型颈部近端1区等效应变率有增高,空置模型颈部近端1区等效应变率增加明显。结论股骨头坏死行髋关节表面置换术时,一定的范围内的骨缺损予以骨水泥填充是安全可靠的方法,缺损在小范围内可予松质骨填充,但随着缺损增加,股骨头和颈部骨折风险急剧增高。Objective To investigate the reliable treatment methods for the femoral head defect during the hip resurfacing arthroplasty,by comparing the biomechanical effects between bone cement filling and cement vacancy using three-dimensional （3-D） finite element analysis.Methods The 3-D finite element model of the normal femur was constructed based on the CT scanning.Four defect models were established by the computer assissted design technology.The defect diameter was 50%of the femoral head diameter in two models, and it was 80%of the femoral head diameter in the other two models.The femoral head defects were dealt with cement filling or vacancy.The models were loaded with the simulated standing stress, and the biomechanical indices of the femoral head and neck were compared and analyzed, including the stress peak and the equivalent strain.Results The stress concentration in the femoral head： in the model of 50%diameter defect, the stress concentration was not significant in the cement filling group, but it was significant in areaⅠof the femoral head in the vacancy group;in the model of 80%diameter defect filled with cement, the stress concentration exceeded 100% in area Ⅰ of the femoral head, while in the vacancy group, it exceeded 1000%in areaⅠ;the maximum stress concentration in areaⅡwas as high as 766.89%.The stress concentration in the femoral neck：in the model of 50% diameter defect, the stress concentration in the femoral neck was between -50% and 50% in both groups;in the model of 80%diameter defect, it was between -50% and 50% in the cement filling group, while it was extremely increased in the vacancy group.The equivalent strain in the femoral head：in the model of 50% diameter defect, the equivalent strain did not chang significantly in the cement filling group, while it increased significantly in the proximal part of the head in the vacancy group;in the model of 80%diameter defect, it increased significantly in the vacancy group.The equivalent strain in the femoral neck： in the model of 50

关 键 词：股骨头坏死 髋表面置换术 股骨近端 有限元分析 应力集中 

分 类 号：R687.4[医药卫生—骨科学]