Finite element analysis of adjacent intervertebral disc stress after single-level and two-level PLIF surgery
Objective To analyze the maximum equivalent stress changes of adjacent intervertebral discs and facet joints after single and double level lumbar fixation fusion using the three-dimensional finite element method.Methods The subjects' CT images of the lumbar spine were imported into Mimics21.0 software in DICOM format,and the three-dimensional model of L2～5 lumbar spine was obtained by using regional growth,differentiation threshold and threshold segmentation.According to the specific parameters of the two in-ternal fixators,two different solid geometric models of lumbar spine fixation were constructed in the modeling software,and the model val-ues and grid division were carried out.The changes of the maximum equivalent stress of the adjacent intervertebral disc and facet joint af-ter the operation of the two different fixation segments were compared and analyzed.Results The average values of the maximum equiva-lent stress of the adjacent upper and lower intervertebral discs in different states after fixation by two different surgical methods was com-pared with the normal value,and the maximum equivalent stress of the adjacent lower intervertebral discs in the two-level PLIF was sta-tistically significant(P<0.05).The mean value of the maximum equivalent stress of the upper articular process of the upper vertebral body and the lower articular process of the lower vertebral body after fixation by two different surgical methods was not statistically signifi-cant compared with the normal value(P>0.05).Conclusion The risk of ASD after two-stage PLIF is higher than that after single-stage PLIF.The greater the stress of the adjacent upper and lower intervertebral discs and facet joints,the higher the risk of developing ASD.
Lumbar fixation and fusionBiomechanicsFinite element analysis
NETL
NSTL
万方数据
