Abstract
Purpose
Evaluation of status of collateral ligament & prediction of post-op alignment is important for partial knee replacement because during UKA the ligament can't be released & overcorrection or severe varus alignment result in poor clinical result. Evaluation of ligament could be done with valgus stress or distraction. The authors compare the stress view & distractive CT scanogram. to know the effectiveness regarding the prediction of final alignment.
Material & Method
19 knee from the 16 people receiving partial knee replacement was studied, we measure the anatomical axis &mechanical axis of the valgus stress view & distractive CT scanogram & post-operative whole leg radiogram.
Result
anatomic axis in preoperative radiograph of a 30-degree valgus load was 7.31 ± 3.33, that of full-length radiograph of postoperative period was 3.11 ± 2.12, there was a significant difference between both groups (p = 0). Anatomic axis in preoperative CT anatomical valgus axis was 2.36 ± 2.04 & that of full-length radiograph of postoperative period was 3.11 ± 2.12, there were not significantly different. (P = 0.209). mechanical axis in preoperative of distraction CT scanogram were 4.15 ± 2.23 & that of post-op full length radiogram was 3.43 ± 2.42,& there were no significant difference between both groups. (P = 0.314) displacement of the mechanical axis of the surgery was 29.27 ± 14.08% in CT,& that of post-op full length radiogram was 34.45 ± 11.9%, there was no significant difference in both groups. (P = 0.261)
Conclusion
InPartial knee replacement, distractive CT scanogram effectively predict the post-operative alignment, & valgus stress view show the overcorrected alignment.
