Department of Radiology, Sungkyunkwan University School of Medicine, Kangbuk Samsung Hospital, Seoul, Republic of Korea.
Department of Radiology, Myongji Hospital, Koyang, Gyonggido, Republic of Korea.
Clin Radiol. 2014 Apr;69(4):391-6. doi: 10.1016/j.crad.2013.11.008. Epub 2013 Dec 17.
To evaluate the clinical utility of the meniscal width to transverse diameter ratio (L/M ratio) of the lateral meniscus in the diagnosis of incomplete discoid lateral meniscus (IDLM) as compared with the arthroscopic diagnosis, meniscal width to tibial diameter ratio (L/T ratio) and conventional lateral meniscus width criteria.
This retrospective study sample included 41 patients with IDLM who underwent knee magnetic resonance imaging (MRI) and arthroscopy, as well as 50 controls with normal lateral menisci. MRI examinations were interpreted independently by two radiologists, both of whom were blinded to clinical information and radiological reports. Assessment of meniscal width (L), maximal transverse diameter of the lateral meniscus (M), and transverse diameter of the tibia (T) was carried out on central coronal sections that were observed to pass through the medial collateral ligament. L/M and L/T ratios were calculated. These results were correlated with arthroscopic findings and analysed statistically using categorical regression analysis and non-parametric correlation analysis. Using arthroscopic findings as the standard of reference, sensitivity and specificity were calculated for: (1) 12, 13, 14, and 15 mm meniscal width thresholds; (2) 40%, 50%, 60%, and 70% L/M ratio thresholds; and (3) 15%, 18%, 20%, and 25% L/T ratio thresholds.
The mean L/M ratio of the IDLM was approximately 67% and was statistically significantly higher than the control (44%). The best diagnostic discrimination was achieved using a threshold of 50%. The mean L/T ratio of the IDLM was approximately 23% and was statistically significant. The best diagnostic discrimination was achieved using a threshold of 18%. The threshold of 13 mm of meniscal width also showed high sensitivity and high specificity.
The use of the L/M ratio or L/T ratio in combination with meniscal width criteria may be a useful method for evaluating IDLM.
评估外侧半月板宽度与横径比（L/M 比）在诊断不完全盘状外侧半月板（IDLM）中的临床应用价值，并与关节镜诊断、半月板宽度与胫骨直径比（L/T 比）和常规外侧半月板宽度标准进行比较。
本回顾性研究样本包括 41 例 IDLM 患者，他们均接受了膝关节磁共振成像（MRI）和关节镜检查，以及 50 例正常外侧半月板的对照者。MRI 检查由两名放射科医生独立进行，他们均对临床信息和放射学报告不知情。在中央冠状位上进行半月板宽度（L）、外侧半月板最大横径（M）和胫骨横径（T）的评估，这些层面通过内侧副韧带观察。计算 L/M 和 L/T 比值。这些结果与关节镜检查结果相关，并使用分类回归分析和非参数相关分析进行统计学分析。以关节镜检查结果为标准，计算出以下各项的敏感性和特异性：（1）12、13、14 和 15mm 半月板宽度阈值；（2）40%、50%、60%和 70%的 L/M 比值阈值；和（3）15%、18%、20%和 25%的 L/T 比值阈值。
IDLM 的平均 L/M 比值约为 67%，明显高于对照组（44%）。使用 50%的阈值可获得最佳的诊断区分度。IDLM 的平均 L/T 比值约为 23%，具有统计学意义。使用 18%的阈值可获得最佳的诊断区分度。半月板宽度 13mm 的阈值也具有较高的敏感性和特异性。
使用 L/M 比值或 L/T 比值结合半月板宽度标准可能是评估 IDLM 的一种有用方法。
