目的研究MRI多征象分析在膝关 节前交叉韧带损伤诊断中的临床应用价 值。方法 回顾性分析我院150例膝关节损 伤患者的MRI图像，由我院两名影像科医 生根据膝关节前交叉韧带损伤的5个直接 征象及10个间接征象进行评价。对150例 患者行膝关节镜检查，比较评价结果与膝 关节镜结果之间的差异。结果 膝关节前 交叉韧带损伤的5个直接征象中，前交叉 韧带不连续、走行异常以及水肿增粗的敏 感性较前交叉韧带消失及萎缩变细差异明 显，具有统计学意义(P<0.05)；膝关节前 交叉韧带损伤的10个间接征象中，均具有 较高的特异性和较低的敏感性，其中PCL 指数、Notch征、半月板后角裸露征及空 髁间窝征等特异性高(P<0.05)。结论 膝 关节前交叉韧带损伤的5个直接征象中以 前交叉韧带不连续、走行异常以及水肿增 粗具有较高的诊断价值，可以作为诊断的 主要依据；膝关节前交叉韧带损伤的10个 间接征象中以PCL指数、Notch征、半月板 后角裸露征及空髁间窝征等具有较高的特 异性，可以作为诊断的辅助依据。

Objective To research the diagnostic value of MRI signs of anterior cruciate ligament injury. Methods MRI images of 150 knee joints were retrospectively evaluated. Two radiologists evaluated all these images for the presence of 5 direct signs and 10 indirect signs. 150 patients underwent knee arthroscopy, compared evaluation results and arthroscopic results. Results Among the 5 direct signs, discontinuity of ACL and abnormal contour of ACL had relative higher sensitivity and specificity (P<0.05); Most of the indirect signs,had relative high specificity but low sensitivity. The following 5 indirect signs, bare area at the femoral origin of the ACL, Notch sign, uncovered posterior horn of lateral meniscus sign, PCL curvature ratio, and entire length of the PCL observed on a single coronal image, had relative higher sensitivity (P<0.05). Conclusion Direct signs were the main clues for diagnosing ACL in juries, and discontinuity and abnormal contour of ACL were the two most valuable signs of a tear. Indirect signs were only for assistant diagnosis and bare area at the femoral origin of the ACL, Notch sign, uncovered posterior horn of lateral meniscus sign, PCL curvature ratio, and entire length of the PCL observed on a single coronal image were the best predictors of an ACL tear．