J Korean Orthop Assoc.  2016 Feb;51(1):96-99. 10.4055/jkoa.2016.51.1.96.

Double-Layered Medial Meniscus

• Kim ST
• Lee SY
• Park MS

• KMID: 2154355
• DOI: http://doi.org/10.4055/jkoa.2016.51.1.96

Abstract

We report on the case of double-layered medial meniscus, which was overlying anterior to mid portion of the medial meniscus. The upper accessory meniscus was connected to the anterior portion of the normal medial meniscus. And its periphery was connected to the joint capsule. The posterior portion of the upper accessory meniscus was connected to the joint capsule. This case demonstrates an interesting and rare anatomical abnormality of the medial meniscus. We report on the case with a review of the literature.

Keyword

meniscus abnormality; medial meniscus; double-layered meniscus

MeSH Terms

Joint Capsule
Menisci, Tibial*

Figure

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  Figure 1 (A) In coronal T2-weighted magnetic resonance imaging (MRI) an additional meniscus was observed in the medial meniscus (arrow). (B) In sagital T2-weighted MRI there was upper meniscus on lower meniscus (arrow).

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  Figure 2 Arthroscopic findings. (A) An additional semicircular meniscus was observed over the normal medial meniscus (arrow). (B) The upper meniscus was cord like round shape (arrow). (C) The upper meniscus extended from anterior portion to mid portion. Its anterior edge was attached to the lower meniscus. Its periphery was connected to the joint capsule and the lower meniscus. Its posterior edge was attached to joint capsule.

Reference

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