摘要
目的研究骶骨部分切除术后骨盆重建的生物力学特征。方法分别构建完整骨盆。经S1、S2之间施行骶骨部分切除术后的缺损骨盆和重建骨盆的三维有限元模型。模拟人体坐位时的负荷,研究3种模型的位移与应力分布变化。结果得到了三个模型中骶岬前方参考点在垂直方向的位移值及整个模型和重建器械的应力分布情况。结论骶髂关节部位的重建可以增强骶骨部分切除术后骨盆的稳定性,并改变骨盆应力分布,降低骶器关节应力峰值,减少术后骨盆破坏的风险。L5椎弓根螺钉与髂骨钉之间的钛棒发生断裂的风险较大,提示术中应当重视弯棒操作,避免钛棒过度成角,防止应力过度集中,减少断棒的危险。
Objective To investigate the biomechanics changes of the reconstructed pelvis after sacrectomy. Methods Three three-dimensional finite element pelvic models were established： （1） a normal pelvic model, （2） a defective pelvJc model on which sacrectomy was operated between $1 and $2 sacral vertebrae, and （3） a reconstructed pelvic model. Sitting posture was stimulated under the load of body weight, and the stress and displacement distributions of these models were calculated and compared. Results The displacement of anchor point on the sacral promontory, the stress distributions of the pelvis and the reconstruction instruments of the three models were all obtained. Conclusion Sacroiliac joint reconstruction can increase the stiffness of the defective pelvic and decrease the maximum stress around the sacroiliac joint, thus reducing the breakdown risk of the defective pelvis. Part of titanium sticks between L5 pedicle screw and iliac screw is the weakest region in the instrument, it is suggested that the bending of titanium sticks should be conducted carefully without forming acute angle and significant stress concentration on the titanium sticks so as to reduce the risk of sticks breakdown.
出处
《医用生物力学》
EI
CAS
CSCD
2008年第1期47-51,共5页
Journal of Medical Biomechanics
关键词
骶骨切除
重建
骨盆
有限元方法
Sacrectomy
Reconstruction
Pelvis
Finite element analysis
