నైరూప్య

Congenital Incomplete Discoid Lateral Meniscus of the Knee Joint - A MRI Case Report

Vinodhini P, Vivek Pandey, and Mamatha H

The knee joint is a compound, double condylar articulation between the patella and the femur divided by the menisci. Lateral meniscus is about 4/5 of a circle, with peripheral vascularization, richly innervated articular horns. The structural arrangement of meniscus defines the biomechanical function of medial compression and lateral tension. During the routine radiological interpretation (MRI) of the left knee joint in a 25 yrs old woman in the department of radiology, Kasturba Medical College, we observed an incomplete discoid lateral meniscus. Discoid lateral meniscus is a congenital intra articular knee disorder, appears as thickened, full crescent shaped disc. It is incomplete due to deficient coverage (<80%) of the lateral tibial plateau. The thickness of the meniscus, its diminished vascular blood supply, weak capsular attachment, makes it more prone to tears. Discoid meniscus is an atavistic anomaly, common in Asian population, in which the meniscus of the knee, predominantly the lateral meniscus, is discoid (3%) rather than semilunar in shape. The abnormality is diagnosed infrequently and may go unrecognized or untreated. Treatment can be of either partial or complete meniscectomy performed either arthroscopically or by open arthrotomy. Management of the disorder should be directed toward the resolution of the symptoms while preserving meniscal tissue and function. Modern surgical techniques enable suturing and preservation of meniscal tissue.