Medial and Lateral Discoid Menisci of Both Knees

Abstract

Discoid menisci on both the medial and lateral sides are rare, and there are very few reports on cases involving both sides. We report a case of a 52-year-old female with medial and lateral discoid menisci in both knees. Arthroscopy revealed the lateral menisci of both knees were complete discoid menisci, and partial meniscectomy was performed. The medial menisci were incomplete discoid menisci, but there were no findings of abnormal mobility or injury; therefore, the medial menisci were observed without treatment. At six months postoperatively, her pain and range of motion restrictions disappeared.

Keywords: Discoid; Knee; Lateral; Medial; Meniscus.

Fig. 1

Plain radiograph showing hypoplasia of the lateral femoral condyle and varus deformity of the articular surface of the proximal tibia. R: right, L: left.

Fig. 2

Full-length frontal plain radiograph revealing hypoplasia of the lateral femoral condyle and varus deformity of the articular surface of the proximal tibia. Both Mikulicz lines were slightly displaced inwardly. R: right, L: left.

Fig. 3

T2-weighted magnetic resonance imaging revealed the medial menisci of both knees were incomplete discoid menisci with a high intensity area in the posterior section (arrowheads). The lateral menisci were complete discoid menisci with a horizontal high intensity area (arrows). R: right, L: left.

Fig. 4

Arthroscopic findings of both knees. The medial menisci were incomplete discoid menisci, but there were no findings of abnormal mobility or injury (A). The lateral menisci were complete discoid menisci (B) and partial meniscectomy was performed, during which a horizontal tear (C) was observed from the anterior to the posterior section. R: right, L: left.

Fig. 5

Plain radiograph showing lateral femorotibial joint space narrowing (arrows) at 1 year and 7 months after surgery. R: right, L: left.