Finite Element Analysis Of The Influence Of Intervertebral Disc Cement Leakage On The Stress Distribution Of Adjacent Vertebrae After Percutaneous Vertebroplasty

Objective:3D model and biomechanical simulation software were used to study the effect of intervertebral disc cement leakage on the stress distribution of adjacent vertebrae during percutaneous vertebroplasty(PVP),and to explore the effects of bone cement leakage and its location on the stability of adjacent vertebrae,so as to provide postoperative risk prediction for bone cement leakage during percutaneous vertebroplasty.Methods:By including the CT data of a patient after PVP and using Mimics Research 21.0,17.0finite element analysis software,the three vertebrae models(T12 vertebrae,L1 vertebrae and L2 vertebrae)after PVP were established,and the diseased vertebrae were L1 vertebrae as the control model.Three models of bone cement leakage to upper intervertebral disc(experimental model a),inferior intervertebral disc(experimental model b)and upper and lower intervertebral disc(experimental model c)were made by digital simulation,and the simulated amount of cement leakage was 1ml,1.5ml,2ml,which were named as low leakage group,medium leakage group and high leakage group.To analyze and compare the stress distribution of the anterior cortical column,the anterior 1/3 cortical column and the central column of the adjacent vertebrae,in order to explore the influence of bone cement leakage on the stress distribution of the adjacent vertebrae after PVP.Results:In the comparison among the data groups of high leakage group,medium leakage group and low leakage group,compared with the control model,the stress of T12 and L2 vertebrae in the experimental model increased,and the difference was statistically significant(P <0.05),and the stress of the three groups of T12 vertebrae and L1 vertebrae was anterior 1/3cortical column > anterior cortical column > the central column(P < 0.05),and the stress of the experimental model a and c of T12 vertebral body was significantly larger than that of the experimental model b(P < 0.05).The experimental model b and c of L2 vertebral body stress were significantly larger than those of the experimental model a(P < 0.05).In the comparison between groups,it can be seen that the stress changes of each vertebral body are as follows: high leakage group > medium leakage group > low leakage group(P < 0.05).Conclusion:Compared with no leakage,the stress change of adjacent vertebrae is relatively larger,and the possibility of fracture is greater.The leakage of bone cement in adjacent upper and lower intervertebral discs during PVP operation can be an important risk factor for new fracture of adjacent vertebrae.The amount of leakage of bone cement is also positively correlated with the stress of adjacent vertebrae.