The Effect Of Body Position Changes On Acetabular Abduction Angle And Its Clinical Significance

Objective:To explore the change trend and law of angles of the acetabular abduction andanteversion by the pelvic rotation angles along the sagittal axial. Improve the plantedaccuracy of acetabular component abduction angle during THA in the posterolateral appr-oach.Methods:1experimental method1.115adult normal pelvic specimens were studied (male8，famale7) including30hips. The angles of the acetabular abduction were measured by different pelvic rotationangles along the sagittal axial. Record and sort data， process the data with SPSS13.0.Statistical analyze the acetabular abduction angles and different pelvic rotation angles by thelinear correlation analysis. Statistical analyze the acetabular abduction angles measured inthe same pelvic rotation angle between male and famale.1.2The pelvic rotation angles along the sagittal axial of normal people were measuredby the radiological measurement at lateral position.60volunteers were posed at lateralposition and the X-ray films of the pelvis were captured by DR. Metal horizontal andvertical line were marked by plumb line to be used as standard when measure angles. TheX-ray films were disposed by DICOM13.0， the angles between teardrop line and verticalline were measured， statistical analyze the relevant data.2Statistical analysis:Date were expressed as the mean±standard deviation for the number of experimentsindicated.The statistical analysis was performed by using SPSS13.0(SPSS，the USA).Statistical analyze the acetabular abduction angles and different pelvic rotation angles by thelinear correlation analysis and make the scatter plot. Statistical analyze the acetabular abduction angles measured in the same pelvic rotation angle between male and famale byindependent-samples T test. Statistical analyze the pelvic rotation angles along the sagittalaxial measured on the X-ray films between male and famale by independent-samples Ttest.For all tests，test level=0.05(2-tailed)Results:1The acetabular abduction angle and pelvic rotation angle showed the positive linearcorrelation by the linear regress analysis and linear regression equation:=47.144+0.942x.2No significant differences were found in the acetabular abduction angle by the samepelvic rotation angle between male and famale（p＞0.05）.3The mean of pelvic rotation angles along the sagittal axial of normal people is5.47°.No significant differences were found in the pelvic rotation angles along the sagittal axialmeasured on the X-ray films between male and famale(p＞0.05).Conelusion:1.The change in the acetabular abduction angles is very obvious when the pelvicrotates along the sagittal axial，The motion of pelvis on the coronal plane should be paidattention to during THA in the posterolateral approach，preoperative and intraoperativebody position should be adjusted properly.2.No significant differences were found between male and famale when the pelvicrotates along the sagittal axial at the same angle. The influence of gender factors can beignored during THA in the posterolateral approach.