Judgment Of Pelvic Rotation And The Research On The Influence Of The Acetabulum Prosthesis Implantation Precision

Pelvic rotation is refers to the pelvis around the body transverse longitudinal axis and the sagittal axis of 3D rotation,its occurrence factors including the various causes of sacroiliac joint malposition,lumbosacral joint dislocation and pubic symphysis displacement,etc.,or the position of the human body caused by various factors is not standard that cause pelvic rotation,judge the pelvis direction of rotation and degree of related experimental study and clinical work is of great significance.Chapter No.l introduces four kinds of X-ray on pelvic rotation method,which is:The SFP Angle(sacro-femoral-pubic Angle,Angle of SFP)to evaluate pelvic rotation,rotation ratio method(Rotation Ratios Method)to evaluate pelvic rotation,width ratio of left and right innominate bone to evaluate pelvic rotation,closed pore ratio method to evaluate pelvic rotation.The article summarizes the rotation tilt measuring methods,and provide reference for clinical pelvic rotation related diseases treatment.Chapter No.2:[Objective]To investigate the differences of acetabulum related parameters between the horizontal plane and true pelvis plane on CT images.[Methods]Hip CT images of 80 normal cases were collected with natural supine position.The direction of CT scanning was perpendicular to the horizontal plane.Bilateral acetabular anteversion angle,abduction angle,centre edge angle(CE angle),acetabulum width,acetabulum depth and angulus acetabularis were measured,as well as the angle between the true pelvis plane and horizontal plane.All CT images were performed three-dimensional reconstruction,then images were collected with the scanning direction perpendicular to the true pelvis plane.The same parameters were measured.Paired t test was used to compare the differences of the outcomes between left and right side of the acetabulum,as well as the ones between the two reference planes.Group t test was adopted to compare the differences of parameters between male and female.Spearman correlation analysis was performed to indicate the association of the parameters differentials and the reference planes angle.P<0.05 was considered as significant difference.[Results]There were no significant differences between the parameters of two sides of the acetabulum in both reference planes.Significance was detected between the genders.In horizontal plane,the abduction angle,acetabulum width and depth were remarkably higher in female(p<0.05).Pelvic tilt was positively correlated with the difference values of acetabular anteversion angle and CE angle,and was negatively correlated with the differentials of acetabulum depth and angulus acetabularis(p<0.05).[Conclusion]Traditional CT measurement of acetabulum parameters may result in errors.More attentions should be paid to during the pre-operative planning by the surgeons.Chapter No.3:[Objective]:To study the relation between the pelvis rotation Angle and left and right iliac width ratio to provide anatomical basis for hip replacement.[Methods]:The left and right iliac width ratio of the 4 pelvis were measured in pelvic X-Ray when facing the 5 different pelvic obliqueness angles.?Results?:the experiments with 4 pelvic when simulating different pelvic rotation Angle left and right sides of the ilium width ratio of the mean and standard deviation werel.57±0.06.1.38±0.08?1.12±0.11?1.09±0.08?1.01 ±0.11.The pelvic obliqueness angle and The left and right iliac width ratio?left iliac width?the right iliac width showed the positive linear correlation by the linear regress analysis and the linear regression equation were Y=8.64+(-1.38)X?r=0.828;Y=9.02+0.076X,r=0.861;Y=0.952+(-0.28)X,r0.882.[Conclusion]Based on the results of the study,the inclination of pelvis was impact of the left and right iliac width ratio.The results provided reliable anatomical basis for total hip arthroplasty.