Murlimanju B V, Nair Narga, Ray Biswabina, Pai Mangala M, Amin Soumya, Pai Shakuntala R
Department of Anatomy, Kasturba Medical College, Manipal University, Bejai, Mangalore, 575004, India.
Anat Sci Int. 2011 Jun;86(2):63-8. doi: 10.1007/s12565-010-0088-0. Epub 2010 Jun 15.
In the present study, the objectives were to study the morphology of the lateral menisci (LMs) in human fetuses from a South Indian population and to verify the developmental etiology of the discoid lateral meniscus (DLM). The study included 106 fetal knee joints which were fixed in 10% formalin. After dissecting the joints, the morphological variants of the shapes of the LMs were macroscopically noted and classified as discoid and nondiscoid. The nondiscoids were subdivided into C-shaped and crescentic. The discoid lateral menisci (DLMs) were divided into complete and incomplete discoid. From our observations, 82.1% of the LMs were found to be nondiscoid. Among them, 62.3% were C-shaped and 19.8% were crescentic. The remaining 17.9% of the LMs had a discoid shape, and among these, 14.1% were incomplete discoid and 3.8% were completely discoid. Bilaterality of the discoid shape was observed in 26.6% of the cases. There was a female preponderance (11:8) among LMs with discoid morphology. In conclusion, the prevalence of DLM according to the present study was estimated as 17.9%. Our findings favor Kaplan's theory, as the majority of the fetuses of various gestational ages had nondiscoid LMs. Even the youngest fetus (CRL 88 mm, 14 weeks of gestation) exhibited a lateral tibial plateau that was incompletely covered by the meniscus, which did not exhibit a discoid shape. We believe that the DLM is anomalous and arises through variant morphogenesis.
在本研究中，目的是研究来自南印度人群的人类胎儿外侧半月板（LM）的形态，并验证盘状外侧半月板（DLM）的发育病因。该研究包括106个固定于10%福尔马林中的胎儿膝关节。解剖关节后，肉眼观察LM形状的形态学变异，并分为盘状和非盘状。非盘状半月板再细分为C形和新月形。盘状外侧半月板分为完全型和不完全型。根据我们的观察，发现82.1%的LM为非盘状。其中，62.3%为C形，19.8%为新月形。其余17.9%的LM呈盘状，其中14.1%为不完全盘状，3.8%为完全盘状。26.6%的病例观察到盘状形态的双侧性。盘状形态的LM中女性占优势（11:8）。总之，根据本研究，DLM的患病率估计为17.9%。我们的发现支持卡普兰理论，因为不同孕周的大多数胎儿的LM为非盘状。即使是最年轻的胎儿（头臀长88 mm，妊娠14周），其胫骨外侧平台也未被半月板完全覆盖，且未呈现盘状形态。我们认为DLM是异常的，是通过变异的形态发生形成的。
