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"
Tibia taking an axial force during walking that is up to 4.7 bodyweight. Its bending moment in the sagittal plane in the late stance phase is up to 71.6 bodyweight times millimetre. Fractures of the tibia can be divided into those that only involve the tibia; bumper fracture, Segond fracture, Gosselin fracture, toddler's fracture, and those including both the tibia and fibula; trimalleolar fracture, bimalleolar fracture, Pott's fracture. In Judaism, the tibia, or shankbone, of a goat is used in the Passover Seder plate. The structure of the tibia in most other tetrapods is essentially similar to that in humans. The