Bird feet and legs only a small extension of the cnemial crest. In grebes both a normal patella and an extension of the cnemial crest are found. The fibula is reduced and adheres extensively to the tibia, usually reaching two-thirds of its length. Only penguins have full-length fibulae. The bird knee joint between the femur and tibia (or rather tibiotarsus) points forwards, but is hidden within the feathers. The backward-pointing "heel" (ankle) that is easily visible is a joint between the tibiotarsus and tarsometatarsus. The joint inside the tarsus occurs also in some reptiles. It is worth noting here that the name "thick knee"
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