RESUMO
BACKGROUND:Currently, the morphologic changes of the discoid lateral meniscus (DLM) remain unclear, and morphological indexes used to evaluate the injuries of DLM stil need to be explored. OBJECTIVE:To compare the MR imaging difference between symptomatic and asymptomatic DLM in adults, and to select reliablemorphologicalparametersfor assessing DLM. METHODS:A total of 36 patients (36 knees) with a symptomatic DLM (study group)and 34 patients (34 knees) with an asymptomatic DLM (control group) were included in this study. GE Healthcare Centricity RIS/PACKS System was used to measure the primary morphological parameters of two patients with DLM on coronal MR imaging. Intergroup comparison was performed with the Wilcoxon test. RESULTS AND CONCLUSION:On the coronal MR imaging, the width of the body portion and height of the free edge of the DLM was significantly increased in the study group compared with the control group (P 0.05). The width ratio of the body of the DLM to the lateral femoral condyle and the height ratio of height of the free edge to the middle of the DLM were significantly increased in thestudy group compared with the control group (P< 0.001), while the height ratio of the peripheral portion to the middle for the DLM was significantly decreased compared with the control group (P< 0.001). These findings suggest that compared with asymptomatic discoid lateral meniscus, the width of the body portion and the height of the free edge for the DLM are increased;however,the height of the peripheral portion which connects with the capsule of the DLM is decreased. The width ratio of the body portion of the DLM to the lateral femoral condyle and the height ratio of the free edge to the middle for the DLM may be reliable morphological parameters for the assessment of the DLM in adults.