The Influence Of The Reverse Contained Buttress For The Accuracy Of Implanting Acetabular Prosthesis

Background and purpose: Reverse contained buttress is usually used inlateral position surgery, especially for those obese patients and extremelyobese patients. Reverse contained buttress is widely used in abroad clinicalwork, however, seldom used in domestic clinical work. Based on theradiographic picture, this dissertation is to study the influence of the reversecontained buttress for the accuracy of implanting acetabular prosthesis.Methods: This research chose two excellent orthopedics surgeons in thedepartment of bone and joint from the First hospital of Jilin University, bothsurgeons are good at THA, the only difference between them is that onesurgeon always use reverse contained buttress in THA, the other one don’t.Under a series of strict selection standard, we retrospectively enrolled100patients who underwent THA in the department of bone and joint from theFirst hospital of Jilin University between June2010and March2014. Eachsurgeon enrolled50patients, and the50patients performed by the surgeonwho used reverse contained buttress were defined as experimental group, theother50patients performed by the surgeon who didn’t use reverse containedbuttress were defined as control group. The method devised by Lewinneck9was used to measure the anteversion and abduction of acetabular components on postoperative plain AP radiographs in experimental group and controlgroup.Results: In experimental group,50patients (37men,13women), themean abduction is41.16±3.026°, the mean anteversion is16.03±4.1325°. Incontrol group,50patients (33men,17women), the mean abduction is40.16±4.225°,the mean anteversion is17.14±5.5172°. There was nosignificant difference in abduction and anteversion between experimentalgroup and control group. And there was no significant difference in clinicalprognosis between experimental group and control group.As to the patients with a BMI of＜25,25patients in experimental group,the mean abduction is41.96±2.150°, the mean anteversion is17.076±3.7875°.11patients in control group, the mean abduction is42.45±2.207°, the meananteversion is16.42±3.701°. In the patients with a BMI of＜25, there was nosignificant difference in statistics and clinical prognosis between experimentalgroup and control group.As to the patients with a BMI of≥25,25patients in experimental group,the mean abduction is40.36±3.569°, the mean anteversion is14.984±4.2711°.39patients in control group, the mean abduction is39.51±4.448°, the meananteversion is17.338±5.954°. In the patients with a BMI of≥25, there was asignificant difference in abduction between experimental group and control group (P=0.026). And there was no significant difference in anteversionbetween experimental group and control group (P=0.973).Conclusions: This research showed that in the patients with a BMI of≥25, the reverse contained buttress can influence the abduction of acetabularcomponent. Due to the reverse contained buttress can provide a platformwhich is parallel with the operation table in the surgery, the protractor for theabduction of acetabular component could place on the platform steadily.Therefore, these made the abduction is more nearly to45°. As to theanteversion, there was no significant difference between experimental groupand control group, because the reverse contained buttress could not provide amore accurate frame of reference.