Abstract
Fetal and adult long bones, the connection between bone surface and surface fibres were observed using a scanning electron microscope. Fetal bones were observed in a 20-week-old fetus. The surface was rough and fibres were attached to the ridges. A small vessel was found in each groove, and each vessel was covered with fibres. There was no difference between the patterns of connection of the metaphysis and diaphysis. In a 40-week-old fetus, the surface had become smooth and lacunae had formed. The surface fibres were buried in the bone, were attached to the edges of the lacunae, or connected the vessel to the bone. There were large amounts of lacunae in the metaphysis. In observation of adult bones, there were a large number of lacunae in the metaphysis and a considerable amount of the lacunae had its own vessel. The surface vessels were covered with fibres. The lacunae in the diaphysis was shallow and not as great as in the metaphysis. The surface fibres of the diaphysis were connected to the collagen fibres of the bone. Also, the fibres were in bunches and were attached to the lacunae. In a 40-week-old fetus, the patterns of connection were almost completely formed and were the same as those of an adult. The roles of the connection between the fibrous layer of the periosteum and the bone surface were to anchor the surface fibres to the bone in order to protect it and to cover the surface vessels in order to protect them.
