Periosteum

The periosteum is an envelope of fibrous connective tissue that is wrapped around the bone in all places except at joints (which are protected by cartilage). As opposed to bone itself, it has nociceptive nerve endings, making it very sensitive to manipulation. It also provides nourishment in the form of blood supply to the bone. The periosteum is connected to the bone by strong collagenous fibres called Sharpey's fibres , which extend to the outer circumferential and interstitial lamellae of bone. The periosteum contains a store of osteogenic osteoblasts, and thus plays a vital part in the healing of fractures.