The knee meniscus is one of two intraarticular cartilage disks of the knee-joint (plural: menisci). Being crescent-shaped, they are located between the femoral and tibial condyles. They are cartilaginous trihedral plates, with their peripheral edge being thick and fused with the articular capsule. The menisci are attached anteriorly and posteriorly to the intercondylar eminence of the tibia. The anterior part of both menisci are joined by the transverse ligament of the knee.
The upper surface of the meniscus is concave, while the inferior surface is flat and lies on top of the tibial condyles. Therefore, the peripheral edges of the menisci follow the configuration of the superior border of the tibial condyles. As a result, the medial meniscus is crescent-shaped, while the lateral meniscus resembles a half of a circumference. Posteriorly, the posterior meniscofemoral ligament attaches the lateral meniscus to the intercondyle fossa of the femur.
Injury to one of the meniscus or both is very common in outdoor sports, such as soccer. Twisting or overextension of the knee-joint can severely tear them. If they get detached, a sudden blockage of the joint occurs, rendering hinge-like movement impossible. Sometimes it is necessary a surgical procedure.
Diagram of anterior aspect of the right knee-joint showing the medial and lateral menisci joined together by the transverse ligament of the knee.
Below, posterior aspect of the right knee-joint, where you can see the posterior miniscofemoral ligament anchoring the lateral meniscus to the femoral intercondyle fossa.
Below, superior aspect of the menisci of right knee showing the cruciate ligaments. Notice the crescent shape of the medial meniscus
