Many people believed that the bone is static and inert, but this idea is incorrect, the organic andmineral components of the bone matrix are continually being recycled and renewed through aprocess called remodeling. This process goes under way throughout life, as part of normal bonemaintenance. Bone remodeling plays a key factor between the activities of osteocytes, osteoblasts,and osteoclasts.
In the adult stage, osteocytes are continually removing and replacing thesurrounding calcium salts. But osteoclasts and osteoblasts also remain active, even after theepiphyseal plates have closed. For the most part their activities have a balance. As one osteonforms through the activity of osteoblasts, another is destroyed by osteoclasts.
In young adult,approximately each year one fifth of the adult skeleton is demolished and the rebuilt or replaced.The turnover and recycling of minerals give each bone the ability to adapt to new stresses.The mechanism that controls the internal organization and structure is osteoblast. Whenever a boneis stressed, the mineral crystals generate electrical fields.
Osteoblasts have an attraction to theseelectrical fields, and once they are in this area they begin to produce bone. Since bones areadaptable , their shapes reflect the forces applied to them. Heavily streeled bones become thickerand stronget, whereas bones not being accessible to ordinary stresses will be deteriorated.Therefore is important to exercise daily to maintain a normal bone structure.