Analysis Of Stability Of The Sacroiliac Complex And Its Biome Chanical Significance Using A Three-dimentional Finite Element Model

Objective: illustrate clinical value and biomechanical significance of sacroiliac complex. Objective: establish finite element model about sacroiliac complex and pelvis , Under bilateral leg standing position through exerting 400N load on sacrum perpendicularly we cut off a couple of ligaments simultaneously every time keeping other ligaments complete, or disconnect all the ligaments on one side. Taking vertical and sagital displacement as evaluating criterion, we obtain these data from several typical nodes and input them to SPSS10.0 for statistical analysis, probing the effect of every couple of ligaments on the stability of sacroiliac joint and analyzing stress variation on the joint surface. Results: The created FEM were meshed is no significant difference statistically in ROM between finite element method and biomechanical experiment. When cutting off every couple of ligaments simultaneously ,sacral vertical and sagital displacement every time are compared with each other and the result is shown as follows: inerosseous sacroiliac ligaments > short posterior sacroiliac ligaments > long posterior sacroiliac ligaments, while anterior sacroiliac ligaments, sacrotuberal ligaments and sacrospinal ligament have no obvious effect on the stability of sacroiliac complex. Conclusion: The created FEM of pelvis and sacroiliac complex reflects objectively real anatomical outline and biomechanical behavior of the pelvis. It helps us make further biomechanical research on the basis. It is of great help to pay attention to the effect of every couple of ligaments on pelvic stability through analyzing sacral displacement and stress variation on joint surface and pelvic ring. Through simulating ligament injury we can understand pelvic traumatic mechanism and keep sacroiliac complexes complete.