Zhang Haisen, Lü Long, Zhang Yu, Xu Yongsheng, Wang Wei, Wei Baogang
Inner Mongolia Medical College, Hohhot Inner Mongolia, 010010, P.R. China.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2011 Jan;25(1):42-6.
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 cruciate-sacrificing self alignment bearing total knee arthroplasty (TKA).
The clinical data were analyzed retrospectively from 40 patients (40 knees) undergoing primary unilateral TC-PLUS SB posterior cruciate-sacrificing self alignment 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) degrees, respectively. The X-ray films were taken to measure PCO and anteroposterior femorotibial translation. Multiple 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.
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) degrees, 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 last 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 established (R = 0.785, R2 = 0.617, F = 61.128, P = 0.000). Anteroposterior femorotibial translation could be introduced 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.
Kinematics after TC-PLUS SB posterior cruciate-sacrificing self alignment bearing TKA with posterior cruciate ligament-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-PLUS SB posterior cruciate-sacrificing self alignment bearing TKA.
观察后髁偏移（PCO）变化及股胫前后平移情况，探讨其对后交叉韧带牺牲型自行对线全膝关节置换术（TKA）患者最大膝关节屈曲范围（ROF）的影响。
回顾性分析2007年1月至2009年6月期间40例（40膝）因骨关节炎接受初次单侧TC-PLUS SB后交叉韧带牺牲型自行对线及负重TKA的患者的临床资料。其中男性18例，女性22例，平均年龄70.6岁（范围56 - 87岁）。病程5 - 14年（平均9.1年）。左侧11例，右侧29例。术前膝关节协会评分（KSS）和ROF分别为48.0±5.5和（77.9±9.0）度。拍摄X线片测量PCO及股胫前后平移。以股胫前后平移和PCO变化作为自变量，最大膝关节屈曲作为因变量进行多元回归分析。
所有切口均一期愈合。患者随访12 - 19个月（平均14.7个月）。末次随访时，与术前值相比，KSS（91.9±3.7，t = -77.600，P = 0.000）、ROF[（102.0±9.3）度，t = -23.105，P = 0.000]有显著差异。术前[（31.6±5.5）mm]与末次随访时[（30.6±5.9）mm]的PCO有显著差异（t = 3.565，P = 0.001）。末次随访时，股胫前后平移为（-1.2±2.1）mm（95%CI：-1.9 mm至0.6 mm）；股骨向前滚动27例（67.5%），无滚动1例（2.5%），股骨向后滚动12例（30.0%）。通过多元回归分析（逐步法）建立回归方程（R = 0.785，R2 = 0.617，F = 61.128，P = 0.000）。股胫前后平移可纳入方程（t = 7.818，P = 0.000），但PCO变化被排除在方程之外（t = 1.471，P = 0.150）。回归方程为y = 25.587 + 2.349x。
TC-PLUS SB后交叉韧带牺牲型自行对线负重TKA术后的运动学表现主要为股骨相对于胫骨向前滚动，这对术后活动范围有负面影响。在TC-PLUS SB后交叉韧带牺牲型自行对线负重TKA中，PCO变化与术后ROF变化之间无相关性。
