Knee joint with ligaments
Human knee joint with bones and ligaments. The knee joint (Articulatio genus) is a rotation angle joint between the femoral condyles (the cartilaginous parts of the thigh bone at the knee joint) and the two flat sockets of the Tibia head (head of the lower leg bone), and also the kneecap (as a sesamoid bone in the tendon of the quadriceps femoris muscle, flipped down in the picture). Two menisci (under the two femoral condyles) even out the incongruence of the articular surfaces. Furthermore, two cruciate ligaments (anterior and posterior) as inner ligaments and two lateral ligaments that strengthen the capsule (collateral fibular and tibial ligament). The knee joint enables flexion and extension as well as (in case of relaxed collateral ligaments) a considerable rotation of the lower leg.
