To Evaluate The Biomechanical Properties Of Osteoporotic Lumber Fracture Treated By Vertebroplasty With Three-dimensional Finite Element Analysis

Objective:To study the biomechanical of preoperative and postoperative osteoporotic lumbar2vertebral fracture treated by percutaneous vertebroplasty with three dimensional finite element analysis.Methods:Select a75-year-old osteoporotic vertebral compression fracture of Iumbar2treated by bilateral percutaneous vertebroplasty with three dimensional finite element analysis.Clinical curative effect is good and2year’s follow-up without new vertebral fracture.Get the preoperative and postoperative CT image data and scan the data with DICOM format for CD burning. Import it into MIMICS image processing software. With the help of ANSYS to construct preoperative and postoperative3-d finite element model of osteoporotic vertebral fracture of lumbar2,Set boundary conditions and loading static load to mimic the physical condition of the lower lumbar spine flexion, lateral flexion, rotating around movement. At lumbar1vertebral above is based on axial load of500N to simulate upper body gravity, and at the same time in lumbar1respectively load anteflexion. extension with50n. m. lateral flexion with40n. m, rotate with15n. m. Finite element calculation. Extraction the cloud stress map of Iumbar2vertebral (disease vertebral),lumbar1and3(adjacent vertebral) before and after operation. Select the point stress value of lumbar1.2.3vertebral body to carry out their own matching t test analysis of the same motion state of stress before and after treatment.Results:We have established three dimensional finite element model of preoperative and postoperative osteoporotic vertebral fracture which has222727units,4node shell element21803.10node unit200315. bar element609. Cement injection into Iumbar2(disease vertebral) when rotating have no influence on stress (P>0.05) and on each movement condition lumbarl.3also have no influence on stress (P>0.05) while increases Iumbar2(disease vertebral) stress when bending, stretching, lateral flexing(P<0.05). Conclusion:A small amount of bone cement injected into the senile osteoporotic Iumbar2fracture can not only increase the vertebral strength for good curative effect bu also have slightly influence on the adjacent vertebral stress.