The knee joint is made up of three bones, the femur (thigh bone), the tibia (shin bone) and the patella (knee cap). The knee joint is a hinge joint allowing two principal actions flexion (bending) and extension (straightening). The meniscus is “C shaped” discs made of tough cartilage called fibrocartilage. They are located on the tibial plateau (top surface of the tibia) between the tibia (shin bone) and the femur (thigh bone).
There is a lateral meniscus which is located on the outside of the knee joint, and a medial meniscus located on the inside of the knee joint. The meniscus plays a role in joint stability by creating a cup for the femur to sit in, and also act as a shock absorber for the knee by spreading compression forces from the femur over a wider area on the tibia. This function helps to protect the underlying joint surface cartilage that lines the bone surfaces from wearing out and developing degenerative arthritis.