The periosteum serves several functions including anchoring tendons and ligaments, assisting the passage of blood into and out of the bone and assist in growth of the bones. The periosteum is an important part of the skeletal system and is found as a membrane along the outside of the bone.
The membrane is made up of irregular dense connective tissue, which is divided into two layers called the fibrous layer and the cambium layer. The cambium layer contains the progenitor cells that develop into osteoblast. The osteoblast are key in increasing the width or length of a bone. They also play a part in healing bone breaks and bone fractures.