Lee Kwang Won, Yang Dae Suk, Choy Won Sik
Orthopedics. 2013 Oct 1;36(10):e1333-5. doi: 10.3928/01477447-20130920-30.
Various shapes of congenital abnormalities of the meniscus have been reported. Among them, the double-layered meniscus is rare. This article describes a 22-year-old man with a double-layered lateral meniscus who reported right knee pain with no history of trauma. The double-layered lateral meniscus included both the upper and lower meniscus. The anterior and posterior edge of the upper meniscus was attached to the lower lateral meniscus, and its periphery was not connected to the capsule and the lower meniscus. In addition, the upper meniscus was dislocated into the intercondylar notch, mimicking a bucket-handle tear. However, the lower meniscus was normal in appearance, so a bucket-handle or horizontal tear of the meniscus was ruled out of the differential diagnosis. Although this is a rare case, clinicians should be aware of this anomaly due to the potential for a double-layered meniscus to contribute to a bucket-handle or horizontal tear of the lower meniscus. Therefore, early diagnosis and proper treatment of a double-layered meniscus are needed before an additional injury occurs to a normal meniscus.
已有多种半月板先天性异常形态的报道。其中，双层半月板较为罕见。本文描述了一名22岁男性，其外侧半月板为双层结构，自述右膝疼痛，无外伤史。双层外侧半月板包括上半月板和下半月板。上半月板的前缘和后缘附着于外侧下半月板，其周边未与关节囊及下半月板相连。此外，上半月板脱位至髁间切迹，类似桶柄样撕裂。然而，下半月板外观正常，因此在鉴别诊断中排除了半月板桶柄样或水平撕裂。尽管这是一例罕见病例，但临床医生应了解这种异常情况，因为双层半月板有可能导致下半月板出现桶柄样或水平撕裂。因此，在正常半月板发生额外损伤之前，需要对双层半月板进行早期诊断和恰当治疗。
