Finite Element Study On Spinal Stability After Healing Of Osteoportic Vertebral Compression Fracture Treated By Functional Reduction Of Traditional Chinese Medicine

Objecttive:1.Using computer finite element analysis(FEA)method for biomechanical study,simulated functional reduction for the treatment of osteoporotic old thoracolumbar vertebral compression fractures with a high recovery of 10%,30%,60% lower than normal,analysis of functional reduction after fracture healing The stress and strain distribution of the intervertebral disc,the fractured vertebral body and the adjacent vertebral body at different reduction levels were analyzed,and the biomechanical properties of the stability of the spine were analyzed.2.The finite element analysis method was used to explore the mechanism of the treatment of thoracolumbar vertebral compression fractures with over-extension and reduction.It provided some theoretical and experimental basis for the clinical application and regulation of this technique.Methods1.CT image data collection: 1 case of normal elderly clinical volunteers and 1 inpatient of orthopedic hospital in our hospital,and 64-slice spiral CT in our hospital was used to scan the upper edge of T11 vertebral body to the lower edge of L3 vertebral body.Save in DICOM format.2.The establishment and verification of 3D geometry: DICOM format images were imported into Mimics16.0 software for vertebral body separation,and then 3D geometric models of T11-L3 with five vertebral bodies were established by using Geomagic studio optimization and Solidworks assembly software.Then,the thoracolumbar vertebral compression fracture was simulated,and the L1 vertebral body was given a certain displacement to cause the fracture.The simulated functional reduction was used to treat the three-dimensional finite element model of the 10%,30%,60% compression fracture of the L1 vertebral height after fracture healing.Verify its validity.3.Establish T11-L3 finite element model: Introduce geometric model T11-L3 vertebral body into Solidworks software for assembly,then establish vertebral cortical and cancellous bone,upper and lower endplate,intervertebral disc,articular cartilage,add spring simulation in ANASYS software Ligaments in various parts.4.Finite element analysis: The normal human T11-L3 model and the L1 vertebral compression fracture model were respectively introduced into the ANASYS software analysis,and the lower edge of the L3 vertebral body was set as a constraint,and a uniform vertical vertical force was applied to the upper surface of the T11 vertebral body.500 N,simulates the load when the human body is upright,and then applies a torque of 7.5 Nm to simulate the load of the human body's flexion,extension,right flexion,and left flexion.Record and compare the stress and strain distribution and displacement of each model under the same physiological load.Results1.The simulation established a normal human body T11-L3 consisting of 5 vertebral bodies,4 intervertebral discs and endplates,articular cartilage and ligaments,which verified its effectiveness,and there is no significant difference between the literature data and the basic biomechanical characteristics of normal human body 3D geometric model.2.The normal human body T11-L3 finite element model was used to establish a 10%,30%,60% compression model of the L1 vertebral body leading edge after functional reduction treatment.The flexion model was flexion,right flexion,left flexion and extension.Next,record the stress,strain,and displacement of the internal vertebral disc,fracture vertebral body and facet joint of the fractured vertebral body fracture.3.The three modified height L1 vertebral compression fracture models after functional reduction and the normal human T11-L3 vertebral body finite element model were compared and analyzed.It was found that 60% of the same physiological load was applied.In the compression model,the stress of the fractured vertebral body and the facet joint is the largest,the strain of the intervertebral disc is the largest,and the displacement of the spine is also the largest,followed by the compression models of 30% and 10%.Conclusions1.According to the CT data,a three-dimensional finite element model of the T11-L3 vertebral body of the normal human spine was established.The load and moment were applied.The validity was verified and met the requirements of normal human vertebral body.It can be used for model processing and biomechanical analysis.2.When the height of the vertebral body returns to 60% lower than normal after functional reduction treatment,the stress of the fractured vertebral body and the small joint is the largest,which may cause re-fracture of the adjacent vertebral body and affect the stability of the entire spine and cause local pain.The intervertebral disc strain in the fractured vertebral body is the largest,which may cause the disc to protrude.3.When the height of the vertebral body recovered to 10% lower than normal after functional reduction treatment,the stress of adjacent vertebral body and facet joint was the smallest,the intervertebral disc strain was the smallest,and the stability of the spine was the best;30% of the compressed vertebral body disc,the fractured vertebral body and the small The stress and strain of the joint are small,and the stability of the spine is good and can be accepted by the patient.