髌骨轴位摄影角度与胫股角相关性回归方程的临床应用评价

Correlation between patellar axial angle and tibiofemoral angle photography:a clinical evaluation with regression equation

目的探讨髌骨轴位摄影角度与胫股角相关性回归方程的临床应用价值。方法 100例患者分为两组,根据回归方程设计制作用于测量胫股角和选择摄影角度的角度测量板。实验组(n=50),按照角度测量板测量的胫股角和对应的摄影角度进行髌骨轴位摄影,测量髌股关节显示情况;对照组(n=50)对以往的髌骨轴位影像的髌股关节显示情况进行测量。测量髌骨轴位影像的髌骨后缘双边线间距。统计对照组和实验组的髌骨后缘双边线间距的均值,采用两独立样本t检验,评价两组均值是否存在统计学差异;按髌骨后缘双边线间距的大小统计两组的髌骨轴位影像的优、良、中、差等级百分比。结果对照组和实验组的髌骨后缘双边线间距的均值分别为(1.82+1.23)mm,(0.99+0.94)mm。对两组数据行两独立样本t检验,经Levene's方差齐性检验,F=5.04,P=0.03,两组总体方差不齐,采用近似t检验t,=3.81,P=0.00,两总体均数的统计学存在显著性差异,实验组的髌骨后缘双边线间距比对照组要小。对照组和实验组的髌骨轴位影像的优、良、中、差等级百分比分别为14(28%)、15(30%)、14(28%)、7(14%);27(54%)、16(32%)、5(10%)、2(4%)。结论髌骨轴位摄影角度与胫股角相关性回归方程Y=60+0.6X可作为髌骨轴位摄影的角度选择方程。根据回归方程制作的髌骨轴位摄影角度测量板可准确确定摄影角度,方便、实用。

Objective To study the correlation between patellar axial angle and tibiofemoral angle photography and to evaluate its clinical significance.Methods The angular measuring plate was fabricated by the regression equation designed to measure the tibiofemoral angle and choice of camera angles.A hundred patients were divided into experimental group（n=50） and control group（n=50） based on use or non-use regression equation.The former underwent patellar axial angle photography according to tibiofemoral angle measured by angular measuring plate and corresponding photographic angle to measure the visuaization of tibiofemoral joint,while the latter underwent the measurement of tibiofemoral joint visualized on previously patellar axial images.The spacing of bilateral patellar posterior margin lines was measured on patellar axial images and the mean values of spacing size acquired from two groups were compared each other.The patellar axial images based on mean spacing size were categorized into four grades i.e.excellent,good,moderate,and poor image.Statistical analysis was performed by two independent samples t test to evaluate whether or not significant difference between two groups.Results The mean spacing of bilateral patellar posterior margin lines（0.99＋/-0.94 mm） in experimental group was significantly less than that（1.82＋/-1.23 mm） in control group（P0.05）.The imaging grades of patellar axial photography in experimental group were 27（54%） of excellent,16（32%） of good,5（10%） of moderate and 2（4%） of poor,respectively,while the corresponding values in control group were 14（28%） of excellent,15（30%） of good,14（28%） of moderate,and 7（14%） of poor,respectively.Conclusion The correlative regresion equation（Y=60＋0.6X axis） between patellar axial angle and tibiofemoral angle photography could be taken as a selectable equation used for determing the patellar photography angle.The angular measuring plate fabricated based on the regression equation can accurately determine the photography angle and it is convenient and practical.