A meniscus is a C-shaped piece of fibrocartilage found in the knee joint, sitting between the femur (thigh bone) and tibia (shin bone). There are two menisci in each knee — the medial meniscus on the inner side and the lateral meniscus on the outer side. They act as shock absorbers, distribute weight, and help stabilize the joint. On ultrasound, the peripheral portions of the menisci can be visualized as triangular, echogenic structures at the joint line. While MRI is the gold standard for meniscal tear evaluation, ultrasound can detect peripheral tears, meniscal cysts, and extrusion of the meniscus beyond the joint margin, particularly during dynamic examination.
Sonography Term