| Popis: |
To study the changes of displacement and stress in the model of lumbar pelvic and proximal femur during lumbar rotatory manipulation.The date of lumbar pelvic and proximal femur CT scan by Mimics 10.01 software was established a lumbar pelvic and proximal femur geometric model, then the model was modified with Geomagic 9, at last the modified model was imported into hypermesh 10 and meshed with tetrahedron, at the same time,add disc and ligaments. According to the principle of lumbar rotatory manipulation,the lumbar rotatory manipulation were decomposed. The mechanical parameters assigned into the three-dimensional finite element model. The changes of displacement and stress in the model of lunbar pelvic and proximal femur under the four conditions were calculated with Abaqus model of Hypermesh 10.1) Under the same condition,the displacement order of lumbar was L1L2L3L5 L5, anterior columnmiddle columnposterior column. 2) Under the different conditions, the displacement order of lumbar,case 3case 1case 4case 2. 3) Under the same conditions, the displacement order of lumbar inter-vertebral disc from L1,2 to L5S1 was L1,2L2,3L3,4L4,5L5S1, as for the same inter-vertebral disc, the order was: second quadrantthird quadrantfirst quadrantfourth quadrant. 4) Under the different conditions,the displacement order of the inter-vertebral disc was L1,2L2,3L3,4L4,5L5S1, but to same inter-vertebral disc: case 3case 4case 1case 2. 5) There were apparent displacement and stress concentration in pelvis and hip during the manipulation.1) The principles of lumbar rotation manipulation closely related to the relative displacement caused by rotation of various parts of lumbar pelvic and proximal femur model; 2) During the process of lumbar rotatory manipulation, the angle of lateral bending and flexion can not be randomly increased; 3) During the process of lumbar rotatory manipulation, all the conditions of lumbar pelvic and proximal femur must be considered to determine indications and contraindications. |
