应用AutoCAD在数字影像上进行下肢力线分析

Intra-and interobserver reliability of analysis of lower limb alignment on digital images using AutoCAD

目的 评价将数字影像直接导入AutoCAD进行力线分析的观察者间与观察者自身信度以及所耗时间,并与传统的X胶片测量方法进行对比.方法 对140膝采用以上两种方法进行前后位和全长相角度测量,每种方法平行测量三次,两名观察者分别独立测量.计算每种方法的观察者间和观察者自身ICC值,以Fisher转换Z检验将两种方法的ICC值进行对比,并将两种方法测量每侧膝所耗时间进行配对t检验.结果 观察者间ICC值AutoCAD法为0.942～0.993,传统胶片法为0.736～0.981,观察者自身ICC值AutoCAD 法为0.937～0.999,传统胶片法为0.759～0.951,对应ICC值AutoCAD法比X线胶片法高,大部分有显著差异（P〈0.01）;两名观察者采用AutoCAD法测量一侧膝关节耗时较传统胶片法平均分别短89.6s和94.3s,均差异统计学意义（P〈0.01）.结论应用AutoCAD在DR数字影像上进行下肢力线分析是一种快捷、可靠的方法.

Objective To evaluate intra-and interobserver reliability of analysis of lower limb alignment on DR digital images using AutoCAD.Methods Angles on AP view and long leg view were measured three times by two trained observers separately using these two methods in 140 knees.The intra-and interobserver intraclass correlation coefficients with 95% CIs of two methods were calculated and compared with Fisher z transformation and Z test.Paired t test was used in comparing time consumption.Results For AutoCAD method,inter ICCs were 0.942？ 0.993 ,intra ICCs were 0.937～0.999.For X-ray films method,inter ICCs were 0.736～0.981,intra ICCs were 0.759～0.951.Corresponding ICCs of AutoCAD method were higher than those of X-ray films method,most of which had significant differences（P〈0.01）.The consuming time of two observers in measuring one knee using AutoCAD method was 89.6 seconds and 94.3 seconds shorter than those using X-ray films method respectively.Both had significant differences（P〈0.01）.Conclusion It was a fast reliable method to assess lower limb alignment on DR digital images using AutoCAD.