摘要
目的 :从生物力学角度 ,采用三维有限元方法 ,研究肱骨外髁在不同体位时的实际受力状况 ,探讨肱骨外髁翻转骨折的发生机制。方法 :利用儿童尸体肱骨作为样本建立肱骨中下部三维空间模型 ,测算肘关节伸直和屈曲位时旋前、中立、旋后等六种体位状况下 ,肱骨远段各点的应力值。结果 :无论何种体位下加载 ,肱骨外髁区的平均等效应力值最大 ,滑车桡侧区次之 ,滑车尺侧区最小 ;且屈曲位时各区应力均大于伸直位。屈曲位后区应力显著大于前区。而伸直位时伸肌腱作用点的等效应力值均较屈曲位大 ,且大了 35 %～ 77%。结论 :肘关节屈曲位跌倒时暴力沿前臂通过桡骨小头 ,向上传导撞击肱骨小头最易引起肱骨外髁骨折 ,并可延及滑车桡侧区 ,而滑车尺侧区较少发生破坏 ;伸直位时则因前臂伸肌群强烈收缩而拉脱外髁致骨折。
Objective:From the agulation of biomechanics,adoptthree-dimentional limited component method to study the actualcondition of force received by the humerus lateral malleolus inthe different postures, to discuss the occurance mechanism ofturning-over fracture of the humerus lateral malleolus.Methods: Apply the humeri of child's corpse as samples to set up the three-dimentional space models of the middle and lower parts of thehumeri. The aim is to measure and calculate the strain value ofthe various points in the far sections of the humerus which is inthe six kinds of postures, such as rotating front, middle erect, rotating back, when the elbow joints are in straight and flexionpositions.Results: Under any posture loaded, the averageequivalent strain value of the humerus lateral malleolus area ismaximum, the next is the trochlear radial area, and the trochlearulnar area is minimum. Besides, the strain of all areas inflexing posture is larger than that of the straight posture. Thestrain in the back area of the flexing posture is greatly largerthan that of the front area. The equivalent strain value in theaction points of the extensor muscles while in straight postureis all larger than that in flexing posture. The range is 35%～77%. Conclusion: When the flexing posture of the elbow joint fell down,the violent force passes through radius microcephaly along theforearm conducts upward and impacts humerus microcephaly. In thiscase, it causes the fracture of humerus lateral malleolus easily. And it may extend to trochlear radial area,while the trochlearulnar area seldom damages. When it is in the straight posture, the strongly shrinking of the extenor muscles group pulls thelateral malleolus out and fracture occurs.
出处
《中国中医骨伤科杂志》
CAS
2001年第3期23-26,共4页
Chinese Journal of Traditional Medical Traumatology & Orthopedics
基金
福建省卫生厅青年科研基金
编号 :98-1-2 5
关键词
肱骨外髁
空间有限元
应力计算
实验研究
Humerus lateral malleolus Space limited component Strain calculation Experiment study
