Simulation Two Interbody Fusion Was Into L4-5 Intervertebral, Comparative Flexion And Extension Analysis Of Stress And Strain

Background:Spine fusion is an important topic in spine surgery. Spinal fixation technique and the invention of lumbar fusion cage contributed significantly to the spinal fusion development。Interbody cages have been certified to restore disc height and to increase stability of the spinal segment, and thereby enhance fusion in the surgical treatment of low back pain,spondylolisthesis and degenerative lumber disease.Concomitantly, the use of these cage devices for lumbar interbody fusion has rapidly gained popularity, cage design and choice of cage material also play a crucial role in long-term results. Techniques of interbody fusion include approaching from anterior, posterior, lateral, posterolateral and transformainal。Objective:By simulating the L4-5 intervertebral was grafted into allogeneic bone and Cylindrical fusion cage, after comparing the size of the stress and strain around the bone and provide mechanical parameters for clinical。Methods:Processing the appropriate allogeneic bone and Cylindrical fusion cage, randomly selected 4specimens for the group into allograft bone fusion; randomly selected 4 specimens for the group into pure titanium cage。Simulation of anterior discectomy L4-5 disc herniation, were implanted titanium cage fusion group and allogeneic bone group。Simulation of anterior lumbar spine surgery in the front lumbar windows, removal of part of the anterior longitudinal ligament, the fibrous ring, complete removal of disc, the L4-5 bone endplate reserved。Four specimens were placed in one of allogeneic bone cage, on the other four specimens were placed in a titanium cage。The 1st measurement point is anterior upper edge of the L5 vertebral body, The second measurement point is anterior lower edge of the L5 vertebral body, The third measurement point is anterior upper edge of the L4 vertebral body, The 4th measurement point was anterior lower edge of the L3 vertebral body, The fifth measurement point was inferior articular process of left L4 vertebral body, The sixth6 measurement point was superior articular process of left L4 vertebral body, The No.7 measurement point was superior articular process of L5 vertebral body, The No.8 measurement point was superior articular process of right L4 vertebral body, The No.9 measurement point was inferior articular process of right L4vertebral body。TheNo.10measurementpoint was inferior articular process of L5vertebral body. Each specimen was imposed on 100Ncm, 200 Ncm moment, strain and stress of each measurement point is musured Statistical analysis used SpSS13.0 software to treat completely statistical。Date was demonstrated x±s。Using completely randomized comparison of data, P <0.05 as significant Statistical difference。Results:Maximum strain and stress was the 1st measurement point, this point is anterior upper edge of the L5 vertebral body; The site was the edge of bone of grafting; Analysis of the site was near the bone of grafting。The L4-5 intervertebral space was slotted and was grafted allograft bone fusion, Causing the stress concentration area, In the Moment, the area is subjected to high stress。Minimum strain and stress was the sixth measurement point。The sixth measurement point was inferior articular process of L4 vertebral body, The measurement points was far away from grafting bone area, Therefore, it was the minimum strain and stress。Conclusions:It was demonstrated that the 1st measuring point:the anterior margin of L5 vertebral body in flexion,and extension was dangerous part, occuring maximum strain and maximum stress。Allograft interbody fusion strain and stress of each point was less than Cylindrical fusion cage。...