The osteoblast, osteocyte, and osteoclast

Bone is constantly remodeling, a process of turnover that is critical to the repair of scars left by fracture and infection, the rapid mobilization of mineral as required for metabolic homeostasis, and the optimization of skeletal mass and morphology relative to the functional demands of the organism. This paper provides a brief introduction to the cellular aspects of bone that make this possible. Outlined are the cells that are responsible for achieving the bone's morphology and mobilizing the mineral stores and the systemic and local factors that modulate their activity. With an improved understanding of how these cells function, new insights into the etiologies of musculoskeletal disorders (eg, pseudarthroses, osteoporosis) and means of treating these conditions can be developed.