Hoffa骨折的CT分型

Hoffa fracture： the CT classification system

目的介绍一种新的Hoffa骨折CT分型，并对Hoffa骨折的CT分型与Letenneurx线分型的组间一致性进行比较、方法随机选取2008年1月至2011年12月收治的20例Hoffa骨折患并的影像学资料（膝关节正、侧位X线片和股骨髁CT三维重建片），呈递给20位由高级、中级和初级临床医帅组成的阅片嚣，以同样的流程分别根据LetenneurX线分型和新的CT分型对Hoffa骨折进行分类，采用加权Kappa系数进行组内一致性检验，比较多个阅片者之间的两种分型的一致性。结果20位阅片行埘20例Hoffa骨折患者的CT分型：Ⅰ型占66．0％，Ⅱ型占30．5％，Ⅲ型占3．5％Ⅰ型刺骨折中涉及b区域的Ib型最多，占50．0％，Ia型占19．0％，Ic型占31．0％；Ⅱ型粉碎性骨折中粉碎骨折块也多出现l在b区域；涉及b区域的骨折在CT分型中总的发生率是67．0％。X线分型：Ⅰ型占31．4％，Ⅱ型占14．3％，Ⅲ型占28．0％，Ⅳ型占26．3％。多个阅片者之间CT分型一致性（Kappa=0．681）较x线分割更高（Kappa=0．261）。结论对于ttoffa骨折，新的cT分型一致性优于X线分型，尤其对于粉碎件骨折患者。

Objective To introduce a new CT classification system we designed for Hoffa fractures and compare the interraler reliability between the CT and X-ray classification systems. Methods A total of 20 isolated Hofll fractures from January 2008 to December 2011 were randomly selected for the present analysis of their imaging data （ameropostefior and lateral X-ray films of the knee joint and three-dimensional CT reconstruction of the tmoral condyle）. At the same time, a total of 20 independent observers （clinicians with junior, intermediate and senior professional qualifications） were selected for classification of the Hoffa fractures in the same manner respectively according to the Letenneur＇s X-ray system and our self-designed CT system. We used Kappa statistics to evaluate the interrater reliability among the clinicians between the 2 classification systems for Hoffa fractures. Results According to the CT classification of the 20 Hoffa fractures by the 20 clinicians, typeⅠ, Ⅱ andⅢ fractures accounted fnr 66.0%, 30.5% and 3.5% respectively. In type 1 fractures, type Ib involving zone b accounted for the most （50.0%）, next by type le （31.0%） and type la （ 19.0% ） . In typeⅡ comminuted fractures, fracture fragments were mostly seen in zone b. The overall incidence of fractures involving zone b by CT classification was 67%. According to the X-ray classification, type Ⅰ, Ⅱ Ⅲ and Ⅳ fractures accounted for 31.4%, 14.3%, 28.0% and 26.3%, respectively. The intelTater reliability for CT classification agreement （ Kappa = 0.681 ） among clinicians was higher than that for X-ray agreement （ Kappa = 0. 261 ）. Conclusion For Hoffa fractures, communicated ones in particular, our CT classification system may be better than the X-ray classification system.