J Korean Orthop Assoc.  2011 Apr;46(2):172-176.

Bilateral Discoid Medial Menisci: Two Different Types in One Patient and Bony Changes on the Medial Tibial Plateau

• Nam TS

Abstract

A discoid medial meniscus is a relatively rare pathology of the knee joint, and bilateral cases are extremely rare. We present one case of bilateral symptomatic discoid medial menisci. Arthroscopy revealed a complete type of discoid medial meniscus in one knee and an incomplete type in the other knee. Ours is a very rare case of bilateral discoid medial menisci with associated osseous changes in the tibia, and it is perhaps the first such reported case in the world. The patient was successfully treated by partial meniscectomy using routine arthroscopic procedures.

Keyword

knee; meniscus; bilateral discoid medial menisci

MeSH Terms

Arthroscopy
Humans
Knee
Knee Joint
Menisci, Tibial
Tibia

Figure

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  Figure 1 Anteroposterior radiograph of both knee shows depression (cupping) of medial tibial plateau (thick arrow), widening of medial joint space (asterisk), and hypoplasia of lateral tibial spine (narrow arrow).

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  Figure 2 Magnetic resonance images. (A) Right knee: coronal image shows discoid medial meniscus with horizontal tear (white arrow) and peripheral tear (asterisk) on superior flap. (B) Left knee: coronal image shows similar findings as of right knee.

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  Figure 3 Arthroscopic findings. (A) Arthroscopic view shows complete discoid type of medial meniscus with peripheral tear (multiple arrows) of right knee. MFC; medial femoral condyle, MM; medial meniscus. (B) Arthroscopic view shows fatty degeneration on posterior horn (arrow) of medial meniscus on the right knee. MM; medial meniscus. (C) Arthroscopic view shows incomplete discoid type of medial meniscus with horizontal tear (arrow) of left knee. MFC; medial femoral condyle, MM; medial meniscus, MTP; medial tibial plateau.

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  Figure 4 Arthroscopic finding of anterior cruciate ligament of right knee.

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