儿童症状性外侧盘状半月板患者前交叉韧带形态及信号变化的MRI影像学研究

Magnetic resonance imaging study on the morphologic and signal changes in the anterior cruciate ligament of children with symptomatic discoid lateral meniscus

[目的]报告儿童症状性外侧盘状半月板患者前交叉韧带（anterior cruciate ligment，ACL）形态及信号的变化特征。[方法]自2008年3月-2012年5月经关节镜及核磁共振成像（magnatic resonance imaging，MRI）证实的儿童症状性外侧盘状半月板36膝（外侧盘状半月板组），以及经MRI证实的外侧半月板形态正常儿童35膝（对照组）被纳入本研究。应用GE Healthcare Centricity RIS／PACKS系统分别测量两组病例在MRI冠状面及矢状面上ACL长度、下止点宽度及体部宽度。比较两组病例ACL形态及信号变化的特征。[结果]外侧盘状半月板组冠状面ACL体部宽度明显小于对照组（t=3．733，P=0．001）；而矢状面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比较差异无统计学意义。外侧盘状半月板组正常ACL走行及形态发生率明显低于对照组（x2=13．019，P=0．001）；而外侧盘状半月板组在冠状面（x2=12．776，P=0．001）及矢状面（x2=10．271，P=0．001）异常ACL走行及形态发生率均明显高于对照组。与对照组比较，外侧盘状半月板组ACL异常信号发生率增高（x2=5．418，P=0．020）。[结论]儿童症状性外侧盘状半月板可以引发ACL的MRI影像上的形态改变和信号异常。

[Objective] To report the morphotogic characteristics and signal changes in the anterior cruciate ligament （ACL） of children with symptomatic discoid lateral meniscus. [ Methods] From March 2008 to May 2012, 36 knees （discoid lateral meniscus group） of children with symptomatic discoid lateral meniscus and 35 knees （the control group） of children with normal lateral meniscus confirmed by MRI were included in this study. GE Healthcare Centricity RIS/PACKS System was used to measure the longitudinal length, tibial attachment width, and middle width of the ACL on sagittal and coronal MRI images. Then, the morphologic characteristics and signal changes in the anterior cruciate ligament between the two groups were compared. [Results] On the coronal image, the middle width of ACL in the discoid lateral meniscus group was significantly smaller than that of the control group. The length, tibial attachment width of ACL on both sagittal and coronal MRI images, and middle width of the ACL on sagittal image was not significantly different between the two groups. The incidence of normal mor- phology of ACL in discoid lateral meniscus group was significantly lower than that in the control group. On the coronal and sagittal images, the incidence of abnormal direction and abnormal morphology of ACL in discoid lateral meniscus group was significantly higher than that in the control group. The incidence of abnormal signal of ACL was higher in the discoid lateral meniscus group than that in the control group. [ Conclusion ] The symptomatic discoid lateral meniscus in children could appear as signal changes and abnormal morphology of the ACL on MR images.