中华医学杂志
中華醫學雜誌
중화의학잡지
National Medical Journal of China
2009年
1期
7-11
,共5页
闫家智%吴志宏%徐日新%汪学松%邢泽军%赵宇%仉建国%沈建雄%王以朋%邱贵兴
閆傢智%吳誌宏%徐日新%汪學鬆%邢澤軍%趙宇%仉建國%瀋建雄%王以朋%邱貴興
염가지%오지굉%서일신%왕학송%형택군%조우%장건국%침건웅%왕이붕%구귀흥
腰椎%内固定器%有限元分析
腰椎%內固定器%有限元分析
요추%내고정기%유한원분석
Lumbar wertehrae%Internal fixators%Element analysis
目的 建立腰34节段的后路经椎弓根螺钉内固定的有限元模型,评估固定前后系统的应力变化,探讨后路内固定对腰椎和内固定器械的力学影响.方法 利用Pro/E三维建模软件模拟脊柱后路的钉棒内固定系统,MIMICS软件模拟手术实际操作,建立后路经椎弓根螺钉固定前后的腰3-4节段三维实体,导入有限元软件ABAQUS中建立三维有限元模型.采用腰4椎体做收敛性分析,建立5种不同网格划分数目的 腰4模型进行验证.分析椎体和螺钉系统在0.5 mPa轴向压力下的力学变化.结果 在均布压力下,腰4模型位移为0.00125815 mm,与基准位移的误差只有0.8167%,模型收敛性好.在轴向压力作用下,固定后的椎体、椎间盘和内固定的应力发生明显变化,椎间盘的应力集中部位由后外侧转向前外侧,固定椎体产生的应力明显减小,应力遮挡效应明显.螺钉根部的上下方,存在着明显的应力集中,且上一椎体固定的螺钉要比下一椎体的螺钉承受应力大.结论 利用计算机辅助系统和有限元分析结合的方法 ,可以模拟腰3-4节段后路椎弓根内固定手术,较直观地观察脊柱后路固定前后系统的力学变化.
目的 建立腰34節段的後路經椎弓根螺釘內固定的有限元模型,評估固定前後繫統的應力變化,探討後路內固定對腰椎和內固定器械的力學影響.方法 利用Pro/E三維建模軟件模擬脊柱後路的釘棒內固定繫統,MIMICS軟件模擬手術實際操作,建立後路經椎弓根螺釘固定前後的腰3-4節段三維實體,導入有限元軟件ABAQUS中建立三維有限元模型.採用腰4椎體做收斂性分析,建立5種不同網格劃分數目的 腰4模型進行驗證.分析椎體和螺釘繫統在0.5 mPa軸嚮壓力下的力學變化.結果 在均佈壓力下,腰4模型位移為0.00125815 mm,與基準位移的誤差隻有0.8167%,模型收斂性好.在軸嚮壓力作用下,固定後的椎體、椎間盤和內固定的應力髮生明顯變化,椎間盤的應力集中部位由後外側轉嚮前外側,固定椎體產生的應力明顯減小,應力遮擋效應明顯.螺釘根部的上下方,存在著明顯的應力集中,且上一椎體固定的螺釘要比下一椎體的螺釘承受應力大.結論 利用計算機輔助繫統和有限元分析結閤的方法 ,可以模擬腰3-4節段後路椎弓根內固定手術,較直觀地觀察脊柱後路固定前後繫統的力學變化.
목적 건립요34절단적후로경추궁근라정내고정적유한원모형,평고고정전후계통적응력변화,탐토후로내고정대요추화내고정기계적역학영향.방법 이용Pro/E삼유건모연건모의척주후로적정봉내고정계통,MIMICS연건모의수술실제조작,건립후로경추궁근라정고정전후적요3-4절단삼유실체,도입유한원연건ABAQUS중건립삼유유한원모형.채용요4추체주수렴성분석,건립5충불동망격화분수목적 요4모형진행험증.분석추체화라정계통재0.5 mPa축향압력하적역학변화.결과 재균포압력하,요4모형위이위0.00125815 mm,여기준위이적오차지유0.8167%,모형수렴성호.재축향압력작용하,고정후적추체、추간반화내고정적응력발생명현변화,추간반적응력집중부위유후외측전향전외측,고정추체산생적응력명현감소,응력차당효응명현.라정근부적상하방,존재착명현적응력집중,차상일추체고정적라정요비하일추체적라정승수응력대.결론 이용계산궤보조계통화유한원분석결합적방법 ,가이모의요3-4절단후로추궁근내고정수술,교직관지관찰척주후로고정전후계통적역학변화.
Objective To evaluate the mechanical response of L3-L4 segment after posterior interfixation with a transpediele screw system. Methods Spiral CT machine was used to conduct continuous parallel scan on the L3-IA section of a 40-year-old healthy male Chinese. The image data thus obtained were introduced into MIMICS software to reconstruct the 2-D data into volume data and obtain 3-D models of every element.. Pro/3-D model construction software system was used to simulate the 3-D entity of L3-L4 fixed by screw robs through spinal podicle via posterior approach that was introduced into the finite element software ABAQUS to construct a 3-D finite element model. The stress changes on the vertebrae and screw under the axial pressure of 0.5 mPa was analyzed. Results Under the evenly distributed pressure the displacement of the L4 model was 0. 00125815 ram, with an error of only 0. 8167% from the datum displacement. The convergence of the model was good. The stress of the fixed vertebral body, intervertebral disc, and internal fixators changed significantly. The stress concentration zone of the intervertebral disc turned from the posterolateral side to anterolateral side. The stress produced by the fixed vertebral bodies decreased significantly. Obvious stress concentration existed in the upper and lower sides of the base of screw and the fixed screw at the upper vertebral body bore greater stress than the lower vertebral body. Conclusions Integration of computer aided device and finite element analysis can successfully stimulate the internal fixation of L3-L4 visa posterior approach and observe the mechanic changes in the vertebral column more directly.
