NURS 3102 Chapter 66: Muscoskeletal Function
6 Feb 2017
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Document Summary
Bone is composed of cells, protein matrix, and mineral deposits. The cells are of three basic types osteoblasts, osteocytes,and osteoclasts. Osteoblasts function in bone formation by secreting bone matrix. The matrix, which consists of collagen and ground substances (glycoproteins and proteoglycans), provides a framework in which inorganic mineral salts are deposited. Osteocytes are mature bone cells involved in bone-maintenance functions; they are located in lacunae (bone matrix units). Osteoclasts, located in shallow howship"s lacunae (small pits in bones),are multinuclear cells involved in destroying, resorbing,and remodeling bone. In an emergent situation, an individual who sustains a traumatic fracture to the shaft of the femur may bleed more than 2 l of blood into the surrounding tissues of the thigh, contributing to hypovolemic shock. There are two basic processes of ossi cation: endochondral and intramembranous. Most bones in the body are formed by endochondral ossi cation, in which a cartilage like tissue (osteoid) is formed, resorbed, and replaced by bone.
