Objective To observe the posterior condylar offset (PCO) changes and anteroposterior femorotibial translation, to investigate the influence of them on the maximum knee range of flexion (ROF) in patients with posterior cruciatesacrificing
self al ignment bearing total knee arthroplasty (TKA). Methods The cl inical data were analyzed retrospectively from 40 patients (40 knees) undergoing primary unilateral TC-PLUSTM SB posterior cruciate-sacrificing self al ignment and
bearing TKA for osteoarthritis between January 2007 and June 2009. There were 18 males and 22 females with an average age of 70.6 years (range, 56-87 years). The disease duration was 5-14 years (mean, 9.1 years). The locations were the left side in 11 cases and the right side in 29 cases. Preoperative knee society score (KSS) and ROF were 48.0 ± 5.5 and (77.9 ± 9.0)°, respectively. The X-ray films were taken to measure PCO and anteroposterior femorotibial translation. Multi ple regression analysis was performed based on both the anteroposterior femorotibial translation and PCO changes as the independent variable, and maximum knee flexion as the dependent variable. Results All incisions healed by first intention. The patients were followed up 12-19 months (mean, 14.7 months). At last follow-up, there were significant differences in the KSS (91.9 ± 3.7, t=— 77.600, P=0.000), the ROF [(102.0 ± 9.3)°, t=— 23.105, P=0.000] when compared with preoperative values. Significant difference was observed in PCO (t=3.565, P=0.001) between before operation [(31.6 ± 5.5) mm] and at last follow-up [(30.6 ± 5.9) mm]. At ast follow-up, the anteroposterior femorotibial translation was (— 1.2 ± 2.1) mm (95%CI: — 1.9 mm to — 0.6 mm); femoral roll forward occurred in 27 cases (67.5%), no roll in 1 case (2.5%), and femoral roll back in 12 cases (30.0%). By multiple regression analysis (Stepwise method), the regression equation was establ ished (R=0.785, R2=0.617, F=61.128, P=0.000). Anteroposterior femorotibial translation could be introducted into the equation (t=7.818, P=0.000), but PCO changes were removed from the equation (t=1.471, P=0.150). Regression equation was y=25.587+2.349x. Conclusion Kinematics after TC-PLUSTM SB posterior cruciate-sacrificing self al ignment bearing TKA with posterior cruciate l igament-sacrificing show mostly roll forward
of the femur relative to the tibia, which have a negative effect on postoperative range of motion. There is no correlation between PCO changes and postoperative change in ROF in TC-PLUSTM SB posterior cruciate-sacrificing self al ignment bearing TKA.
Citation： ZHANG Haisen,LUuml,Long,ZHANG Yu,XU Yongsheng,WANG Wei,WEI Baogang. INFLUENCE OF POSTERIOR CONDYLAR OFFSET AND ANTEROPOSTERIOR FEMOROTIBIAL TRANSLATION ON KNEEFLEXION AFTER POSTERIOR CRUCIATE-SACRIFICING SELF ALIGNMENT BEARING TOTAL KNEE ARTHROPLASTY. Chinese Journal of Reparative and Reconstructive Surgery, 2011, 25(1): 42-46. doi: Copy