The Research Of Influence Factor Of Selecting Cementless Acetabular Component

Objective:Research the influence factor of selecting cementless acetabular component size in THR(Total Hip Replacement),so as to provide reference for selecting appropriate size acetabular component preoperatively and intraoperatively.Methods:A record of 806 patients undergoing 1011 primary THR in the Bone Disease Department of the Third Hospital of Hebei Medical University from January 2013 to June 2016 were collected through the Electronic Medical Record System from the Medical Record Department of the Third hospital of Hebei Medical University.In 74 patients(93hips)with periprosthetic fracture,periprosthetic joint infection,prosthetic loosening,dislocation,prosthetic abrasion,cement acetabular component,broken acetabular wall,impact bone grafting of acetabulum,lost of follow-up and incomplete medical records were excluded.In the record of 732 patients(918 hips),186 patients with bilateral hips and 546 patients with unilateral hip involves 466 male patients(592 hips)and 266 female patients(326 hips).The ratio of male to female is 1.75:1,age range is from 18 years to 85 years,average age is(50.24±0.43)years.Then age,gender,height,weight,operation side,diagnosis of the hip disease and the size of acetabular component applied in the operation were collected and recorded in Microsoft Office Excel 2003.The patients were divided into different groups with respect to Age(<45 years,45-59 years,60-74 years,75-89years),Gender,Side of operation,Diagnosis of the hip disease(femoral neck fracture,ONFH,osteoarthritis of the hip,DDH,RA,AS with hip joint stiffness).Then the influence of gender,operation side,age and diagnosis of the hip disease on acetabular component size and the correlationanalysis between acetabular component size and height,weight,BMI were analysed by using SPSS 20.0 software.Results:1 The size of 918 acetabular components presented normal distribution.2 The size of acetabular components applied in different gender were significantly different(P<0.001),the size of acetabular components applied in male group was significantly greater than those in female group.(table 1)3 The size of acetabular components applied in different operation side was different,right side(50.11±2.45)mm was greater than left side(49.93±2.32)mm,but the difference was not so significant(P=0.261).(table 2)4 The size of acetabular components applied in different age group was different,60-74 years group was smaller than the other groups,but the difference was not so significant(P=0.41).(table 3)5 The size of acetabular components applied in different hip disease was different,the size in AS with hip joint stiffness group(51.38±1.70)mm was the greatest among all groups,then hip joint osteoarthritis group(50.30±2.42)mm,ONFH(50.16±2.17)mm,femoral neck fracture(49.26±2.13)mm,RA(49.00±3.70)mm,and the smallest(48.32±2.09)mm was DDH group,and there was significant difference in acetabular component size between AS with hip joint stiffness group and the other groups.(table 4)6 There was linear regression between acetabular component size and patient's height(R2=0.364),the regression equation was Y=16.661+0.200X;also there was linear regression between acetabular component size and patient's weight(R2=0.134),the regression equation was Y=44.720+0.075 X,but was no correlation with BMI(correlation coefficient0.053,P=0.112).(table5,table6,table7)7 The size of acetabular component applied has linear correlation with height(X1),gender(X2),age(X3),weight(X4)and diagnosis of the hip disease(X5),and gender was the most influential factor on the size of acetabular component,the linear regression equation was(table 8):Y =30.277+0.119X1-1.628X2+0.301X3+0.016 X4+0.15 X5.Conclusion:1 The size of acetabular components applied in different gender was significantly different,the component of male group was greater than the female group.2 There were no significant difference in the size of acetabular components applied in different age groups or different operation side.3 There was linear regression between acetabular component size and patient's height and weight,but has no correlation with BMI.4 The disease of the hip joint was the influence factor of acetabular component size,the size of acetabular component in AS with hip joint stiffness group was the greatest in all groups,and the smallest was in DDH group.5 The size of acetabular component applied has linear correlation with height,gender,age,weight and diagnosis of the patients,and gender was the most influential factor on the size of acetabular component.