Animation showing the location of cancellous bone. This zoom in starts with a wide view of the legs showing muscles and blood vessels, before approaching the tibia (shin bone), then into the sectioned head of the tibia to reveal the cancellous bone. Cancellous bone, also called spongy or trabecular bone, is formed of thin interlinking struts called trabeculae. This gives it a low density and a large surface area. The spaces are highly vascular and are often filled with bone marrow, responsible for blood cell production. Cancellous bone is generally found within the ends of long bones, contrasting with the harder and more structural cortical (or compact) bone, which typically forms the hard outer surfaces. Clip made from K003/6206, which has a transparent alpha channel background.