Popliteus muscle assists in flexing the leg upon the thigh; when the leg is flexed, it will rotate the tibia inward. It is especially called into action at the beginning of the act of bending the knee, inasmuch as it produces the slight inward rotation of the tibia, which is essential in the early stage of this movement. When the knee is in full extension, the femur slightly medially rotates on the tibia to lock the knee joint in place. Popliteus is often referred to as the "Key" to unlocking the knee since it begins knee flexion by laterally rotating the femur
Triple tibial osteotomy to distribute load evenly across the surfaces; these are crescent-shaped discs of cartilage facing each other from side to side across the joint. They are thicker at the outside and with a thin inner aspect and they also have nerve fibres that help to tell the brain how much load is getting transmitted through the joint. The medial (inside) meniscus is often damaged with a long-standing cruciate ligament rupture because it is firmly attached to the tibia and gets crushed during abnormal cranial movement of the tibia. The lateral (outside) meniscus is more firmly attached to the femur and does