Haversian System

[Continued from above] . . . majority of interior long bone tissue, in addition to that of the hip and vertebrae. It is also called spongy or cancellous bone because of its soft, spongy texture. Cortical bone, however, is dense and very hard. It is the second of the two types of bone and forms bone surfaces. Periosteum is the fibrous membrane of connective tissue that snugly covers all bones, but it does not cover articular surfaces (where bones come in contact with each other). The articular surfaces are covered with cartilage, which prevents bones from rubbing together. The periosteum also contains attachment sites for muscles, ligaments, and tendons. For adults, the periosteum is responsible for forming new bone as a result of injury or infection. And in children, the periosteum is critical to new bone formation, as well as configuring the shape of bone. A Volkmann's canal is one that allows the transmission of blood vessels (or capillaries) from the periosteum into the bone. A nutrient artery is an artery that supplies the medullary cavities of long bones.