Memory Biomechanical Study Of Acetabular Three Dimensional Memory Internal Fixation System In Treating Acetabular Fracture--3D Model Construction, Mechanical Simulation And Finite Element Analysis

Objective: To find the method of pelvic three dimensional element model construction and discuss its memory biomechanical and clinical significance. Method: One wet pelvic sample from corpse was scanned by CT, 1 mm thin and all images of every cross-section pelvic layer was obtained, and pelvic model was constructed by means of Ansys7.0 software. Results: The constructed 3D pelvic model was clearly reflected the real pelvic anatomy and biomechanical behavior, it was divided into 251 247 nodes,232 435 units. Conclusion: The construction of pelvic three dimensional model can provide true pelvic model for the research of normal mechanical behavior or internal fixation mechanical basis after fracture.Experiment 2 Three dimensional finite element analysis of pelvis loaded by static stress and its biomechanical significanceObjective: To explore the mechanical behavior of pelvis loaded by static stress and provide the mechanical basis for clinical analyzing and judging pelvic mechanical distribution and static stress affected. Method: By means of computer simulation method, reading input from constructed pelvic three dimensional model into three dimensional finite element analysis software ANSYS7.0, calculated the pelvic mechanical behavior and analyzed the main stress value, stress distribution and pelvic unit displacement in the direction of main stress when unilateral anterior superior iliacspine, double anterior superior iliac spine, unilateral positive backside of ilium, double positive backside of ilium was foaded by 1000N static stress. Result: When unilateral anterior superior iliac spine loaded, the stress transmitted from the suffered point to cacroiliac joint, no stress transmitted to acetabulum, pubis and ischium. When double anterior superior iliac spine extruded, stress transmitted to three directions, separately was direction of anterior superior iliac spine to ala ossi ilii, direction of anterior superior iliac spine to cacroiliac joint, the top of acetabulum and superior branch of pubis. When unilateral positive backside of ilium loaded, stress transmitted to three directions: vertical direction of ilium, from ilium to carcroiliac joint direction, and the same side of superior branch of pubis. When double positive backside of ilium loaded, stress transmitted to four directions: vertical direction of ilium, from ilium to carcroiliac joint direction, acetabulum and the same side of superior branch of pubis. Conclusion: Analyzing the stress distribution of pelvis and units displacement when static stress loaded, which can provide internal fixation point for pelvic fracture treatment and try to understand the stress distribution of pelvis. Experiment 3 Three dimensional finite element analysis of pelvis loaded by transient stress and its biomechanical significanceObjective: To explore the mechanical behavior of pelvis loaded by transient stress and provide the mechanical basis for clinical analyzing and judging pelvic mechanical distribution and transient stress affected. Method: By means of computer simulation method, reading input from constructed pelvic three dimensional model into three dimensional finite element analysis software ANSYS7.0,calculated the pelvic mechanical behavior and analyzed the main stress value, stress distribution and pelvic unit displacement in the direction of main stress when unilateral anterior superior iliac spine, double anterior superior iliac spine, unilateral positive backside of ilium, pubic symphysis was loaded by transient stress, the stress region was 0~8000N, peak value was 8000N,time range was from Oms to 40ms.Result: When unilateral anterior superior iliac spine loaded by transient stress, 0~10ms,stress distributed from posterior superior iliac spine to anterior superior iliac spine, and on the last 10ms,there are greater stress distribution around cacroiliac joint, acetabulum andpubic branch. When double anterior superior iliac spine loaded, between Oms and 10ms,stress distribution from anterior superior iliac spine to ilium, on the peak value 10 ms and t...