Periosteum (periosteum) - connective film surrounding bone on the outside. Has extensive functional meaning - is a source bone formation during the growth of the bones in the thickness of children, participates in the formation of callus with diaphyseal fractures, as well as in the blood supply to the surface layers of the bone. Histologically in the periosteum there are two layers (outer - adventitia and internal - fibrous, osteoplastic), rich in nerve endings and blood vessels. In the periosteum woven tendons of muscles and ligamentsthat attach to the bones.
When injuries periosteum in the places of contact with the skin (the crest of the tibia, the back surface of the elbow and others) experiencing a sharp pain, swelling and hemorrhage with subsequent growth of cells and formation of bone substance. Traces from injury persist long as small bumps.
Tumor periosteum are rare, benign - fibroma, angioma (see), mesenchymal; malignant - periosteal sarcoma (Veretennikova, osteogenic, fibrosarcoma). Inflammatory processes are transferred to the periosteum with the surrounding tissues when the abscess, the abscess, osteomyelitis, tuberculosis and other