Bone formation requires a template for development. This template is mostly cartilage, derived from embryonic mesoderm, but also includes undifferentiated mesenchyme (fibrous membranes) in the case of intramembranous ossification. This framework determines where the bones will develop.
What does bone growth and remodeling depend on intake of?
Normal bone growth is dependent on proper dietary intake of protein, minerals and vitamins. A deficiency of vitamin D prevents calcium absorption from the GI tract resulting in rickets (children) or osteomalacia (adults). Osteoid is produced but calcium salts are not deposited, so bones soften and weaken.
What factors affect bone growth and bone remodeling?
Bone growth factors affect the process of bone remodeling. These factors include insulin-like growth factors I and II, transforming growth factor beta, fibroblast growth factor, platelet-derived growth factor, and bone morphogenetic proteins. Bone volume is determined by the rates of bone formation and bone resorption.
What does bone formation depend on proper supply of?
It has long been recognized that bone growth (including endochondral ossification during development) and repair occur in association with a rich vascular supply. Conversely, impairment of the blood supply is well-known to reduce growth and repair, cause bone loss and, ultimately, necrosis (2,3,5,7,8,10,11,16).
What are the 3 main things that affect bone remodeling?
Bone remodeling is thought to be regulated by many factors including nutritional status, humoral factors, and biomechanical stress. However, the involvement of the autonomic nervous system, mainly the sympathetic nervous system (SNS), in the modulation of bone remodeling is beginning to receive more attention.
What are the steps of bone remodeling?
There are five phases in the bone remodeling process: ACTIVATION, RESORPTION, REVERSAL, FORMATION, and QUIESCENCE. The total process takes about 4 to 8 months, and occurs continually throughout our lives.