中文摘要：

目的：分析成人症状性外侧盘状半月板损伤患者前交叉韧带（ACL）形态及信号的变化特征，并初步探讨其发生机制。方法：自2009年5月至2011年11月，经关节镜及MRI确诊的成人症状性外侧盘状半月板损伤32膝（外侧盘状半月板组），和经关节镜和MRI证实外侧半月板形态正常无损伤的另外32膝（对照组）被纳入本研究。应用GE Healthcare Centricitv RIS／PACKS系统分别测量两组病例在MRI冠状面及矢状面上前交叉韧带长度、下止点宽度及体部宽度。比较两组病例前交叉韧带形态及信号的变化特征。结果：外侧盘状半月板组冠状面ACL体部宽度显著小于对照组（P〈0．01），矢状面ACL长度、下止点及体部宽度及冠状面ACL长度、下止点宽度与对照组相比，差异无统计学意义（P〉0．05）。外侧盘状半月板组冠状面及矢状面的ACL走行及形态异常发生率显著高于对照组（P〈0．01，P〈0．05）。与对照组比较，外侧盘状半月板组ACL信号异常发生率显著升高（P〈0．05）。结论：成人症状性外侧盘状半月板损伤可以引发前交叉韧带走行、形态及信号异常，其发生可能与外侧盘状半月板损伤移位并挤压前交叉韧带有关。

英文摘要：

e To report the characteristics of the morphology and signal of anterior cruciate ligament （ACL）in MRI of adults with symptomatic discoid lateral meniscus injuries. Methods From May 2009 to November 2011, 32 knees of adults with symptomatic discoid lateral meniscus injury （discoid lateral meniscus group）were treated by arthroscopic plasty in our hospital, and 32 knees of adults with normal lateral meniscus（the control group）confirmed by arthroscopy and MRI were enrolled in this study. The longitudinal length, tibial attachment width and central width of the ACL on sagittal and coronal MRI images were measured by GE Heahhcare Centricity RIS/PACKS System. The morphology and signal of ACL were compared between the two groups. Results The central width of ACL on the coronal MRI image in discoid lateral meniscus group was significantly smaller than that in control group （P 〈 0.01 ）. The length and tibial attachment width of ACL on both sagittal and coronal MRI images and the central width of the ACL on sagittal image changed insignificantly between the two groups. The incidence of abnormal direction and abnormal morphology of ACL in discoid lateral meniscus group were significantly higher than that in control group（P 〈 0.01 and P 〈 0.05 ,respectively）. The incidence of abnormal signal of ACL was significantly higher in discoid lateral meniscus group than in control group （P 〈 0.05）. Conclusions The symptomatic discoid lateral meniscus injury in adult could lead to abnormal direction, changes in morphology and signal of ACL,probably caused by the displacement of the discoid lateral meniscus and extrusion of the ACL.