股骨前轴作为全膝置换股骨假体旋转对位标志的可靠性研究

Research on the reliability of the anterior femoral axis as reference axis to guide the femoral rotational alignment in total knee anthroplasty(TKA)

目的:在MRI上测量全膝置换股骨假体旋转对位骨性标志,研究股骨前轴作为全膝置换股骨假体旋转对位骨性标志的可靠性。方法:78侧正常成人膝关节,行磁共振扫描,在横断面图像上定位经股骨上髁轴、Whiteside's前后轴、股骨后髁轴和股骨前轴。测量Whiteside's前后轴、股骨后髁轴、股骨前轴相对于经股骨上髁轴旋转的角度,比较它们相对于经股骨上髁轴的可靠性。结果:股骨前轴相对于STEA内旋(9.61±3.36)°,相对于CTEA内旋(13.32±3.27)°。Levene检验提示股骨前轴分别与股骨后髁轴、Whiteside’s前后轴相比,相对于经股骨上髁轴的变异性有显著差别。结论:股骨前轴作为全膝置换股骨假体旋转对位标志的可靠性差。

Objective：To measure the femoral rotational bony landmark on magnetic resonance image,in order to determine if the anterior femoral axis is more consistent relative to the transepicondylar axis than the posterior condylar line and the Whiteside s line.Methods：78 normal knees of Chinese individuals were studied.The images of the knee were obtained by magnetic resonance image.The angles measured on traverse sections included：PCA,posterior condylar angle;CTA,condylar twist angle;ASA,angle between the perpendicular of APL and STEA; ACA; angle between the perpen-dicular of API, and CTEA;AFSA, angle between AFA and STEN AFCA, angle between AFA and CTEA. Compare the consistence relative to the transepicondylar axis between the anterior femoral axis and the posterior condyIar fine or the Whiteside＇ s line. Results： AFSA： （9.61±3.36）° , AFCA：（13. 32±3.27）° . Levene test showed that there was significant difference in variability between the anterior femoral axis and the AP axis or the PCL for referencing the transepicondylar axis. Conclusion： The reliabililty of the anterior femoral axis as referece axis to guide the femoral rotational alignment in TKA is poor.